I remember when trying to play this game a while back, that there were issues running it on new PC's. Specifically that timed events played out much faster than they should (like there was one thing with escaping an explosion as I recall). And that bug made some scenes impossible.

Has that been fixed?

Yes.

However, specifically for the Police Maze (Shooting Range) an original bug was fixed on top of that so:
- In "Easy" mode you will get the original experience. The targets will be quite slow and it may take up to 20 seconds for the first target to appear.
- In "Normal" or "Hard" difficulty you will get the bug-fixed behavior, which restores the proper timings of the targets, thus making them faster and more challenging (!)

Currently, by default (launching the game, with no prior saves) the game starts in Normal mode difficulty.

To choose difficulty (this currently happens only when starting a new game) you need to go through the KIA Load Game screen (hotkey: F3) and select the appropriate Difficulty under "New Game".

The explosion scene and the *other* notorious scene in Act 4 will work as in the original (without issues).