Jon,
I just noticed on Cyrus the other day (1 y.o. nosy be) that he has some discoloration on the bottom of a rear foot. He has a terrible habit of climbing the screen even though he has plenty of branches, etc. There is one side he climbs on as if he can't figure out a better way to get where he is going. Due to this, he has broken some toenails and now I am thinking he may have cut his foot. Not sure if it is from the screen climbing but can’t figure out what else - though he does a lot of roaming on his jungle gym, which I need to check for sharp pieces.
Anyway, it is more like a "blood blister." As if there is blood under his skin. I agree, getting a pic would be hard, I have a he** of a time looking at it daily and he is quite used to being handled.
As for the diarrhea and the excess drinking it is worth a trip to the vet, b/c diarrhea can cause dehydration, which can be a real problem. I recall from an earlier thread there was a discussion about how you are finding it difficult to maintain humidity and several of us made suggestions. I think I even posted a pic for you of the humidifier setup I have. I STRONGLY recommend you get the humidity issue in hand - winter is just beginning.
Carlton's suggestion for travel in the cold is one way. I use a styro box(got from my vet that some stuff was shipped in!) that is lined with t-shirts (don't use towels as the toenails can get caught) and a small branch. I buy the hand warmers at local discount store (usually 4 of them for about $1.50 or $2.00) a lot cheaper than the regular heat packs and easier to get. Before I had the styro box I put one smaller box in another larger one and placed bubble wrap and styro peanuts between the two to insulate. I would put a warmer in the bottom cover with t-shirts, branch etc. Heat up the car and keep it warm. Once at the vet you can take out one or two t-shorts and ask a tech if they would toss it in their dryer to warm it up for the trip home (both my vets have done this for me.). When I had Luna she was at the vet often in the winter months and it was a 45 minute drive each way. Now I see a vet that is much closer.
As for your gutload you definitely need to improve it and you may be dusting too much - what about calcium? Your list is sort of confusing. Go to the link in my sig for links to articles as well as the things we need to know to troubleshoot your setup.
Sorry so long, but I don’t stop by as often as I used to and wanted to cover it all! Carlton and k may have to take it from here as I may not return til tomorrow :-/
btw, here is the humidifier pics again



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Chameleon Help & Resource Info
1.0 Nosy Be Panther Chameleon - Cyrus
0.1 Veiled Chameleon - Luna. She's now hanging from her big jungle gym in the sky
1.0 Beardie - Darwin
1.1.1 Side-blotched lizards - Ana and Stan
0.2 felines - Kyndra and Lita
0.1 African Clawed Frog - Skippy
0.1 Chilean Rose Hair Tarantula - Rosa Leigh, Died 4/21/06 
0.1 Goliath Bird-Eater Tarantula - Natasha, donated to science 4/4/06
?.? Pinktoe Tarantula - no name yet