If i were BG... I would forget about Frolov. Montreal needs to get bigger and tougher up the middle. I would go after Marleau for Plekanec and Halak, which i think helps both teams, SJ needs to reduce salary and add a second line centre and a backup up goaltender.
OR
I would trade A.Kotstitsyn for Jordon Stall. Montreal needs a big centre and Pittsburg needs a goal scoring winger. I think this helps both teams as it addresses a need for both teams, plus the salaries are the same.
As for the cap... Montreal could always send down Laraque and Metropolit to the minors and save 2.5 million.
It's funny how everyone says how we should have keep Koivu and Kovalev but's just keep in mind, that the guys we got are younger, healthier and played for coaches that stress a team, puck possession system. Lou and Sutter in NJ, Keanan in Calgary, Torts and Renney in NY.