This system always worked flawlessly with 4.8, but upon install of PRO 5.0.507, the start menus disappear, i.e. click on start, menu appears displaying usual windows items, such as programs, documents, settings, etc. When you mouse over programs for example a menu listing of installed programs should appear. All that appears is a thin outline of where the menu box is supposed to be.
Un-installing PRO 5.0.507 restores windows to normal operations. Just removal of Avast, no system restore is necessary.
Anyone seen this before, or have any ideas? OS is XP 64bit SP2, FX6200 video, AMD micro
Install 5.0.545 
Yes the new version released this morning (my time) definitely fixes this problem.
Thanks AVAST!