No glue gun I've ever seen could melt solder, let alone the components themselves. Though if you move the glue once it sets it's bound to bring along anything attached to it.
Three more RAM chips? What, you mean like a 48mb upgrade? Had no idea you could do such a thing, thought you needed a full extra set of four.
When I finally got my RAM upgrade working everything was fine and dandy for a few days then suddenly it went back into the rebooting routine. Double checked the chips over and over, finally had to remove them to go back to normal operation. I've tried attaching again a couple of times since with no luck (if you discount the fact that the box still works after each try

). Getting rather hard now that the original solder on the pads is long since gone.
Why not take a look the thingy the solderless connects to, and see where that trace leads? Then you can bypass the whole thing with a wire. If it's accesible enough you can even just hold it in place while you see if the console boots up, and if it does then there's your problem.