Hiya. I'm type 1 and an also on Novorapid and levemir. I was out on Metformin SR about a month ago for similar reasons. Haven't had problems with sweating, but it does make me very, very lightheaded and nauseous. I've got an appointment with my doctor this week to discuss coming off the stuff.
I knows it's still relatively early days, but I have seen no benefits whatsoever and I have felt awful ever since I started taking the damned stuff.
If I were you I would definitely mention to sweating to your doctor. They might try putting you on the slow release version, which apparently has less side effects (or so I have been told).
Anyway, good luck with it!
Em