The "threat detected" are false postives by a couple of antivirus. Something to do with ren'py and the way it works. I posted a topic about it.
"I made a full scan here: https://www.virustotal.com/gui/file/6702bbb07156d090569cc0320e73b78c7a882cdcc2d362d3bc2ff24e211d52cc
Only Cylance and Jiangmin show "unsafe". If your antivirus show "unsafe", it's a false positive. The game is clean. No virus."
It should not touch your log files. As for the voice acting, it's by Chloé Guerin.
I'll still ask on the Ren'py discord 'cause the whole log file issue is strange.
Update: Get this awnser. "I think it [ren'py] writes to its own log file as it starts up, but what might aggravate anti-virus on Windows is using self-voicing because I think that tries to write a vbscript file and then execute it." My game don't use self-voicing by default but it does use the "voice" audio channel.
Update again (so sorry) : Maybe the Steam demo might not give you troubles, then again it's the same files.