http://www.williamfeely.info/wiki/DXGL
It's pretty simple to use. Install and add Starcraft.exe in the program.
Only problems I saw so far is messed up menu when you're creating a game in battle.net, but you can still do it with hotkeys. Also the screen seems to be little cutoff at the bottom in game, but nothing special. And the double click doesn't work -.-
Btw, if game seems little sluggish, make sure the vsync is off in your graphic card settings for BW.