Most succulents get darker color in appropriate amount of sun. There are many different sempervivums, more than 3000 named cultivars. Some are very similar looking. They are Alpines, and grow in mountains at approx. 3000-8000m. Maybe you would find some if you went for a hike in the mountains :) Plant that was red may have not get as much sun as it can take. SE exposure sounds good, but if there are any trees or buildings, they could filter some of the sun. Even some railings on the balcony could be obstructing the sun. Morning sun is usually not as intense. Ppl in warm zones have sometimes problems because of the heat, and keep them in shadier spots. I have them probably in too much sun, it is open area with E,S and west unobstructed exposure. I hardly ever water them, usually if it doesn't rain for about a week. Maybe you are watering to much? In Germany, the climate is good for them. I would keep them on the balcony whole year round. I see from the photos that they are growing well, and there are many offsets/chicks. In 2nd photo, many are very open: if plant wants more sunlight, it opens up - flattens, so there is bigger area to get the sun. Colors also lighten up, gets greener if plant was darker, or even very light green. This happens with many succulents. Here is photo of the same plant in poor light and in lots of sun: They should be acclimatized to stronger sun, or they get a sunburn. But now days are getting shorter, and sunlight is not as intense.

Thanks everyone! I've started putting the pot in the east-facing window when I go to bed so it gets the sunrise light and then into the west-facing window in the afternoon when it can get the sunset light. It should now be getting a lot more direct natural light than it had been. That skyline sunrise picture of Manhattan shows the unobstructed light it now gets in that window. It doesn't start getting into shade until near midday. The west-facing window (where it had been in my home office) has trees and a building across the street, so it gets less exposure depending on time of year. What should I be looking for to tell if it is working? Thickening of the stalk? Leaf clusters closer together? What about coloring? I see a little red-brown on the tips of the leaves. Since we have two egress exits, we don't have fire escapes. There really is no practical means of keeping it outside. If I don't see improvement by switching windows, supplementary lights may be the way to go. The cutting is shriveled, so maybe it didn't make it? It's green and hasn't gotten worse. There are roots and I've sprayed that specific spot to keep it watered. I guess time will tell.

howdy joy! Nice to see you over this way lol I took a fallen leaf a few weeks back..I felt so darn guilty about it...It didnt live either..so I guess that was my karma..I wont do it again..I still ..weeks later..feel really super guilty! i'll say the gritty mix that is mentioned a lot here was a godsend! I have all of my succulents in that gritty mix. I do have a few that need way more water. But I just couldnt keep them alive in soil. Right now I only have leaf propagating in a small layer of soil. Now I know you are an AV grower so I'll say ..I dislike av soil alone..I think its worse than just regular potting soil. You water it and it just compacts. I just recently changed two leaves that I'm trying to grow from just plan av soil into my av/perlite mix. I could be wrong but I think folks here steer away from peat

From the pictures, doesn't look like anything is really wrong. Old leaves are supposed to droop and die, then new ones replace them. The Pleiospilos with the flower bud is blooming out of season so it's all mixed up, plus it needs full sun to get the blooms to open, plus it likely is in root shock from the repotting so no surprise it isn't performing at its best. You really should put each plant into its own pot, they don't all share the same growing needs so you can't really take care of them properly that way. Second thing is try to ID what you have and learn about their growth needs. Reading and learning is the key. Don't be discouraged by the inevitable early failures. Read more about appropriate soil mixes, pots, sun and temperatures. If you have the ability to grow these outdoors they will be much healthier than indoors. Succulents are not good houseplants. They are good at tolerating poor conditions but that doesn't necessarily make them for a windowsill. x