hey the headset turn on when you plug the charge? if not try seeing if all the cables didn't disconnected somehow.
when i did the mod on my h2100 i made a mistake and pulled the wire that connect direct to the soundboard, but i soldered it again and worked fine.
another thing, after i did the mod, i try to turn on and the battery wasn't charged at all, so i first thought that i fucked up the mod but i put the headset to charge for about 1-2hours and the battery started to hold the charge normal again, so try leaving charging for a bit.
its a great mod, i'm getting about 30+ hours of using, insanely good...
(sorry for my english btw, i'm still learning xd)