StarCraft II minimises itself after opening Whenever I try to open up StarCraft II, the updating screen appears for a few seconds on 50%. The window then disappears, but it is still shown as open in the dock (light is on under the icon). How can I fix this problem?
Have you tried a full re-install of StarCraft? Have you ensured that you have all updates, particularly graphic driver updates, are installed?

Additionally, you can also find several troubleshooting steps at OS X Daily which includes a few close descriptions of the issue you described.