No.
1. I basically ignored it, moving the file to a directory I don't scan and awaited the new VPS and program update, no problem after that.
2. having already installed the program, I deleted the program's setup self-extracting exe file. None of the files that were extracted had any sign of infection.
3. I didn't send the file to avast.
Your problem is similar, using an unpacker to look inside the .exe file, the wrong one possible, this could give a false positive. I believe that it is the exe file extension (assumed that it's exe) that is causing it to choose the wrong unpacker.
You don't say what program created the zipfile (if known), if you created it, downloaded it, its name and full path or when and how it was detected, etc.
Those more knowledgable will then be better able to help and avast hopefully correct.