1) Is there a place I can go to find a list of known issues and workarounds? I saw this same problem in a youtube let's play with Avery, but I don't know how he solved it!

2) Anyhow, in Tarant, headed south from inside the gates, towards the warehouse where you kill the rats... and suddenly I am all by myself. I go back to find Virgil and Sogg stuck to a wall. They are unresponsive. So I save/reload - no help. So I save/exit/launch/reload - no help. So I save/exit/reboot/launch/reload - no help.

Now I can go back to an earlier save, but what if it happens again? I'd like to solve this before moving on, if possible.

Companions automatically teleport to your position when they are too far from you.

I think this is the thing where they are unresponsive because there are rats inside that they notice and are trying to attack, but obviously there's a wall inbetween.

When near them, hitting F5 will make them stop trying to attack the rats. Then they should follow normally, but might not engage in combat until directly ordered to (F2 I think). Followers are not good listeners, so when using any of the F-key party commands, you have to be somewhat near them and you might have to issue the same command multiple times.

Yes, that was it. Thanks!

Don't forget that companions will always teleport directly to you if you are simply far enough away, too. That can solve a ton of problems, trust me.