You can try a smaller icon size (16×16) and differnet skins.
If you see that the isuse depends on the skin then can have your custom skin (check the documentation for more details). OIf that's the case I'd recommend to use an existing skin as base of your skin.
Also, upgrading QWP to 5.6 (or 5.7 that is going to be out next month) would solve the problem.