What is the best sealant to use that can handle it all? I have to take mine apart again just to put them back together because of condensation getting in there. I was thinking about reheating them maybe through the oven, but I don't know what temperature and for how long that will allow the old sealant to be reused and easily allow me to put that glass back in there.

faust i would say 150degrees in 3 min intervals. heat then test, heat and test, and heat and test.

as for adhesive i dunno