Are the bulbs soft and mushy???
Also it would help if you got a tripod for your camera!!

Camera????? What's that??? These were taken with the only digital "camera", as you people call it, I've got handy, a mobile phone with a lovely 2 mega pixels!!!

But seriously, not mushy yet. The suspect "spike" is slightly soft and water emerges when it's poked, but the affected main bulb is still firm. This only started a few days ago I suspect, though.

You have performed drastic surgery at the wrong time of year. Winter is coming and growth prospects are limited till spring arrives.

There is another thread where Richard is talking about dividing/repotting Cymbidiums now where it it is spring in the Northern Hemisphere.

What to do? I do not know because i do not grow Cyms. Apart from the good advice that you will get here. Perhaps visit one of the local orchid Societies that can be found in this link and ask the Cymbidium growers for advice.

I can offer little, apart from no fertilizing and reduced watering till spring..

Here is a link that might be useful: Path to 90 orchid Societies in NSW

Thanks for the link Arthurm!
No, I wouldn't think of repotting now, I only repotted another cym because her roots were entirely rotted through and this was the last even mildly warm weather that I'd have before she was totally DEAD. That was an emergency Autumn repot.

But this young lady is a new plant, I'm assuming she developed this while in transit. She didn't look great when she got here, but I didn't think it would develope into this.

Anybody?

I guess if the pseudobulbs are still firm, then that's at least one positive sign. It's not uncommon for the bulbs to abandon a flower spike, especially if it's too hot (either during the day or at night). I have lost quite a few spikes during the 2 weeks of hot weather in March but the "rot" never spread to the bulbs.
As for the current condition of your plant, the yellowing of the leaves could be seasonal but could also be due to a change in culture, especially if the orchid has come from interstate. But also exposure to different light levels can stress a cym.
If I were you, I would give the plant maximum protection, put it in a shaded area that's covered so it doesn't get wet when it rains (I am assuming you are growing this plant outdoors). Water the orchid once or twice a week, it sits in a big pot which may hold quite a bit of moisture and thus cause root rot. If you are unsure, leave a skewer in the medium and pull it out every now and then to check if the medium is still wet. Apart from that, just monitor the plant and the growth of the flower spike. The good thing about cymbidiums is that you can grow them from back bulbs, so even if your plant loses all its leaves, you can always bring it back.
Good luck and keep us updated.

Thanks cymbilover. It has started to rot a bit in the roots, so as a last resort before repot I've sprayed it with Mancozeb, I'm just hoping that may stop or slow it down until Spring.
Yup, it did come from interstate, so the poor thing is adapting to a rather large change. I am growing it indoors, just took it outside to take the pics.

Unfortunately, I have no experience growing cymbidiums indoors. It's too much hassle providing them with supplemental light and controlling the temp to prevent bud blast. Assuming you bought your plant from one of the SA or Vic growers, who usually grow cyms outdoors in a hothouse, bringing it indoors is definitely a massive change in conditions and I am surprised it hasn't abandoned the bigger spike as well. Anyway, I am sure you have your reasons for growing this plant indoors and as long as you are aware that you can't just leave your plant on the kitchen bench or window sill and expect it to do well, you should be ok. I guess the North American growers on this forum can give you more advice on lights and watering frequency.

Hmmm.... Don't know about your theory on abandoning the larger spike Cymbilover.... I've got a few sitting around here and their spikes have shot up, in one case there's a beautiful healthy new spike. I do live in a house where each room has at least one 3/4 wall of glass, also the light in my area is rather wonderful, so this may be why. My main concern on growing it indoors is airflow.

Time to say that almost no one grows Cymbidiums indoors in Sydney. They are outdoor plants apart from bringing them inside to enjoy while they are blooming.

I do grow some orchids indoors all year because outside is a death zone but they are Phalaenopsis species and hybrids and are lower light orchids.

Why not Cymbidiums indoors?
Lack of light (the human eye is a hopeless light meter).
Lack of air movement
Lack of daily temperature ranges and seasons.

Here are some notes for cultivation in the Sydney, Australia area.
CYMBIDIUM Culture Notes

These notes cover Hybrid Cymbidiums ( Standard, Intermediate and Miniature). Cymbidiums are the most commonly grown orchids in the Sydney area. To grow them successfully they require three important factors, fertilizer (food) water and light.

LIGHT
Cymbidiums should be grown under 50% shadecloth or under the shade of a tree that provides broken or filtered light. If you notice that the foliage of your plants have a tinge of yellow that is a indication that your plants are receiving the correct amount of sunlight. This combined with your watering and fertilizing program should give you flowers in the winter months. However, if the foliage is a bright green that is an indication that the plant is receiving too much shade and should receive more light. The more sunlight hours your plant receives the greater the flowering prospects.
FERTILISER
Use Aquasol as recommended by the maker and apply from spring through to mid winter. Or, if you are able to procure Campbells Orchid Fertilizer use the Blue Powder (high in Nitrogen) from about August through to the middle of December. The high Nitrogen content of the fertilizer promotes plant growth. On ceasing to apply the blue powder then switch to Campbells Yellow Powder (high in Potassium). The high Potassium content initiates and promotes flower formation and growth. It is essential that the makers recommendations be followed. Ensure regular fertilizing, about every week. Before fertilizing your plants give them a thorough watering and about one-hour later apply you fertilizer.
WATERING
This is the most difficult aspect of orchid growing. It is dependent on many factors  growing media and prevailing weather conditions. Generally the plants should have a slight element of moisture but not wet all the year round. It will be a general rule that in the winter months watering should be done about once a week and as the weather starts to warm up through Spring and into Summer the frequency of watering should be increased to a maximum of daily watering in the height of summer.

Water early in the day so that your plants will be dry by nightfall. If the weather is overcast, refrain from watering.

BENCHING
Plants should never be allowed to sit on the ground as the drain hole of the pot will soon get clogged up and retain excess amounts of water which will lead to root and rot. Place your plants on a brick, or on a bench.

POTTING MIXES
Buy a good quality potting mixture from a reputable orchid nursery or garden centre. The mixture should be open and allow water to drain through freely. Generally a potting mixture should last two years.
POT SIZE
Chose a pot size appropriate to the size of your Cymbidium. It is important that the roots just fit into the pot. If the pot is too large, the mixture will not dry out between watering, the roots will remain constantly wet and the plant will be lost.
REPOTTING
This should be undertaken in September/October, after flowering when the new growth commences. When dividing the plant it is recommended that about four green bulbs form each new division. Should smaller divisions be used you will setback the growth program and not have flowers in the next season. Cut off all dead roots and try to save as many live roots as possible, though new roots will develop and replace those that have died. DonÂt bury the bulbs of the division in the compost, but ensure that the bulbs are firmly placed in the compost. A shaky plant will not develop roots and growth. Do not water your new division for a few days. Keep the plant out of direct sun and mist the foliage. You may apply some Nutricote (3-4 month) to the top of the pot. A dessert spoon of this is adequate.

PESTS & DISEASES
Like most things orchids are prone to pests and diseases.
VIRUS
Some plants which have yellow spotting or markings on their foliage may be infected with virus  a common virus is Cymbidium Mosaic Virus (abbreviated as CyMV). There is no cure for this virus and could spread through your entire collection. If you have doubts you could consult with the Royal Botanical Gardens, Sydney or any orchid society by taking the plant or infected foliage to them. Viruses are spread through cutting instruments. It is essential that all cutting tools be sterilised by flaming them after each cutting operation.
PEST CONTROL
Pests cause damage by sucking the sap from the cells of the plant tissue or by attacking the foliage.
RED SPIDER MITE
The under side often leaves become speckled and silvered. Flowers become deformed and spotted. A fine webbing develops when infestations are very heavy. Pale yellow/green minute mites with a prominent dark spot on each side of the body. Mites turn red in winter. They are present all the year round. Warm dry conditions promote infestations.
MEALY BUG
Small fluffy sucking insects which often hide in crevices at the base of the foliage on the inside of the developing new growth. They are present all the year round.
SCALE
A small soft or hardened sucking insect which clings to under surface of the foliage.
FUNGUS DISEASE
Plants have black areas on the leaves

PEST AND DISEASE CONTROL
Consult with a garden centre or an orchid society. When using chemicals exercise extreme caution and follow the manufacturerÂs instructions.
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I'm still keeping them indoors........ I'd rather just gift them off if they start to show signs of distress.

But thanks for the tips. Interesting reading.