Is it possible or not to install 2015.10.2.2216 without skype? I'm going to do clean install, but previous posts are frightening me.
Of course it is possible. The very post in front of yours shows how, the very first screen of a clean install has the option. Uncheck the Skype box and also click the Custom Installation button - not the big Blue one, but the small insignificant Grey one.
This gives the opportunity to uncheck many options and tools if you don't require them.
Another point, if you that concerned/frightened about this, then running a beta version of avast may not be a good idea. Whilst the greatest majority beta testing in avast hasn't had any major issues for me, you have to be aware of the risk in any beta testing on a live system, not a test system.