this beta is something indigestable
how can avast! guys make uch o poor beta...its not worth calling it a beta even...its cr*p 
For heavens sake it a sodding beta, I have never heard so much whinging, if you don't like or accept what can happen with beta builds then don't take part.
I have been using avast for over seven and a half years and the betas have generally been stable, unlike many other betas. Essentially the problem is with the installation setup file. When I had the thing installed it worked just fine on the tests that I managed to do before actually testing the program update, which rolled back to 6.0.1289.
So I await the change in that installation package and I will try it again.