I installed Avast!4 on my 3 PCs and for some other people who I help in case of PC problems. With W98, W2k and with WinXP. In all cases the install screens of Avast were hided behind other screens. I only experienced that Avast was busy because of the sign in the bar between start and the systemtray. I had to click on that to get the Avast install screen in front.
Originally I used Avast 4 Beta (as invited to test Avast4) and did in that time not experience the same.
Sorry if I don’t use the proper words, but I only have the Win packages in Dutch and so I am not familiar with the English words for these items.
I just installed Avast today to try it out, and the same thing happened to me. I double-clicked on the installer in Explorer and had to minimize Explorer to see the install screens.
Well, for me it was just the installer (the setup program).
I double-clicked the downloaded file to install Avast and waited for the install dialog to appear. After waiting a few seconds, I minimized (or closed, don’t remember) Explorer and found the install program running, waiting for my input.