Yesterday I experimented a little with an old portable BOINC v6 app found here: https://portableapps.com/node/17295

Worked OK with SETi@home, but didn't work with WCG (as it's a v6). Also app_config didn't work, as that came with v7.0.xx. Well I needed it to run on M5000, as it's a 4GFLOPs card on a work computer.
So today was looking to find something that could work better & on the same link (which I dug out again) found a guy that made portable app from v7.4.42 (lower post from 2nd Apr 2017).

Got that unzipped & started. Works great, WCG linked with no problem on E5 Xeon (4C/8T) & SETi@home now works on 4 WUs at a time with M5000...probably can do more, but have to check that out.

Hope I helped someone with the app. Just be sure not to over do it & that you have some kind of understanding with the admin of your network.