Lag on Ubuntu 12 - what's causing it?

Besides games running at around 10 frames per second both in preview and exported something odd is goign on with the mouse cursor as well. Some times it get’s stuck as either a hand icon or a resize icon.

gpu intelhd4000
cpu i5
ram 8 gb
hdd 1 tb

is the events causing lag?

Are you testing native games or web games in a browser?

Native game.

Ok, which version of Game Develop are you using?

3.3.70, the main download for ubuntu on the frontpage.

Just for lulz: launch the Windows version through PlayOnLinux. Is it lagging more or less?

Actually, it runs really well once I actually got it running (the preview in window function didn’t work).