I've played the game a bit, but not had the issues you've mentioned. When the game was first released I ended up with the Russian version as the default, and it took a while for this to be resolved, but I use the v1.1.2 'Rhaa Movis' version now and it basically plays as expected, though there is some graphics tearing on the initial cutscenes, but nothing that's worthy of mentioning as a problem.

Kultar appears in the adjacent cell, offering words of advice and commenting on the 'gobblers', and after he is released he is present for a while and never seems to be in armour or rushing over to kill the main character.

You seem to have a rogue version there. Which version is installed on your system?