Do you have a substrate in the cage? You said that there is no brown poop...just urates...coming out of him...so I'm wondering if it could be an impaction?
You said..."I have been dusting about every other feeding. I just read about that i should only dust them about once a week because it can raise dangerous using it to much"...from supplements, D3 and preformed vitamin A are the two that you have to worry about building up in the system.
You said..."He used to be by my window and would get the morning sun"...sunlight that passes through glass is not going to provide any useful UVB.
You said..."For calcium i use Rep-Cal Phosphorus-Free Calcium with Vit.D3, for Multivitamins i use Rep-Cal Herptivite with beta carotene"...its usually recommended that the insects be dusted at most feedings with a phos.-free calcium powder, twice a month with the vitamin powder you mentioned and twice a month with a phos.-free calcium/D3 powder. The insects should also be gutloaded/fed a nutritious diet. Crickets, roaches, superworms can be fed a wide assortment of greens (dandelions, kale, collards, endive, escarole, etc.) and veggies (carrots, squash, sweet red pepper, sweet potato, zucchini, etc.).
Phos., calcium, D3 and vitamin A are all important players in bone health and important in other systems in the chameleon as well and they need to be in balance. You need to look at what you feed the chameleon, what you feed the insects and what you supplement when trying to attain a balance.
The most commonly recommended UVB bulb is the long linear tube fluorescent Repti-sun 5.0. A regular household incandescent bulb (in a hood) of a wattage that provides the right temperature in the basking area is all that is needed for heat.