This profile says not to use UVB....but I have always used it and as long as they can move out of it, I doubt that it will do any harm...
http://adcham.com/html/taxonomy/species/r-brevicaudatus.html
For gutloading crickets...I use a wide assortment of greens (dandelions, kale, collards, endive, escarole, mustard greens, etc.) and veggies (carrots, squash, sweet potato, sweet red pepper, celery leaves, zucchini, etc.).
Since many of the insects have a poor ratio of calcium to phosphorus its important to dust the insects at most feedings with a phos.-free calcium powder.
Since they should produce D3 from their exposure to UVB, I only dust lightly twice a month. D3 from supplements builds up in the system and leads to problems.
I also dust lightly twice a month with a vitamin powder that has a beta carotene source of vitamin A. Beta carotene (prOformed) sources of vitamin A can not build up in the system like prEformed sources can. Excess prEformed vitamin A may interfere with the D3 and push a chameleon towards MBD.
Calcium, D3, vitamin A and phos. are all important players in bone health and need to be in balance. You need to look at the supplements, what you feed to the insects and what you feed to the chameleons when balancing them.
Look at the Reptocal...it may have prEformed vitamin A in it (such as acetate, palmitate).
A BIG WORD OF WARNING...these chameleons can play dead very effectively when startled or handled. People have even thrown away the bodies thinking they are dead only to have them get up and walk away after.
These are adorable but short-lived little chameleons...I hope you enjoy it!