Sweet Home New England, you're very kind, and I'm really happy the blog was helpful to you. As you know most of the tips originated with gardenerwantabe, laserfan, and other early purchasers of the kit. It's great that we can all help each other by posting on the web!

I have saved links to these posts that show solutions for snow load bracing (in case you haven't already found them.) Wet, heavy snows can be too much for the HFGH, so folks in snowy areas add additional interior bracing, specifically to support (roughly) the centers of the roof studs. Each HFGH owner applies their own creativity to the problem.

Polcat has a very handsome solution for snow load bracing:
Snow Roof Photo by polcat

Here are Rosepedal's threads about snow load bracing:
Snow Load Brace...
Midwest snow storm...

Web4deb has a wonderful blog about building and modifying the HFGH in amazing ways. This part of the blog mentions modifications for snow load:
The Adventures of Bigelow Brook Farm

Some other GardenWeb threads about snow load solutions and/or problems:
Snow, How Did Your GH Make Out?
HFGH 10x12 Need Roof Studs
Harbor Freight Aluminum GH, Need some advice for Michigan

In addition to roof support, some folks in snowy climates find that the sliding doors can freeze shut, especially in wet icy conditions. This has only happened to me once in 8 years, but I live in a warm climate. Ice accumulated in the bottom door track and nothing moved for 18 hours (I was pretty sure wrenching the doors free would damage the soft aluminum frame.) I have never caulked my panels in place, so I always know in a worst case scenario I can remove a side wall panel and enter the greenhouse that way, in an emergency (heater failure, for example.)

Some HFGH owners have engineered ways to replace the sliding HF doors with hinged storm doors, if the frozen sliding doors were a frequent problem. I have seen a few posts in the greenhouse forum in GardenWeb with photos. Doesn't look like a super easy adaptation, but anything is possible with these kits, with a little time and determination (and a few extra dollars.) Here are a few links to photos:

Yorkie89's door replacement photos are in this thread:
Ripping out the doors...HFGH

Web4deb also made the kit sliding doors work as hinged doors; scroll down to the last entry:
New doors on the greenhouse

As it happens, I'm a bit worried about snow load for my own HFGH this year, because my roof panels have been recently damaged by two hail storms (two hail storms, in two weeks, is that really necessary?) The resulting perforated panels are pretty weak, thanks to some quarter-sized hail, but I had no time for a real re-roof, with cold temps approaching, and a gh chock full of cacti. So we've just finished covered the existing roof with 6ml UV greenhouse plastic, to get through the winter. In our desert climate we usually don't get heavy snows, but if we do, we'll be out there running up the heaters, and doing some emergency interior bracing. Mr. Mudhouse says we can do something fast, if we need to. On we go!

I hope your winter weather is kind to you, and your new greenhouse!

Sheri