the only problem am having with this game after about a month on playing is the npc companion .
its really hard to keep him on track my neck actully ach from looking behind on every corner to
check if he got lost or not . really bad . or is it vikas bug only ?

A couple of questions from me to help resolve your issue:

1) Are you setting your actor fade really low?
2) Are you sticking to roads and paths or jumping over things that your follower can't navigate?

Things like this are really annoying. If you notice he has not been there for a while, just wait for a few hours (ingame time) he should reappear. When he disappears, he is probably fighting an enemy that you just didn't notice, ex. wolves.

Hope this helps
-walrus

it get stuck were there is ladders like mines or so yes when i stopped sprinting it helped