In Autotech (at least on Gamer mode), you need to get rid of the guard by taking soap and mop from the closet and using both items on the bucket. But I've encountered three glitches in this section:
1st (sometimes) - If you get caught, PD will quit to desktop without any error message.
2nd (sometimes) - After using soap and mop on the bucket, the game will lock up.
3rd (always) - If you take care of the guard without triggering first two glitches (this may require multiple tries), the cutscene will play correctly, but the interface graphics will screw up. Entering and quitting Movement Mode (at least if the size is set to full screen) will fix this.
Is there any way to fix that glitches, even if getting the 3rd one allows you to continue the game normally?

The glitches you've encountered was also present in the retailversion of the game, which I still have in my posession. Usually you got through them by saving and reloading a lot in Autotech and if you did get a glitch, you always hoped it was the third one you describe, as you'd be able to get a bit further and save again inside the office.
You can try to change the videosettings in the configfile, and running the game in compatmode for win98 to attempt to avoid the glitches with the GoGversion.

The general rule with games in the nineties was always save often to avoid having to play through some parts more than once.
Sadly, most games nowadays have gotten us quite spoiled since they either autosave often, or don't crash at all.

My best tip is therefore save often, at least every five or ten minutes to avoid having to play through again and again.

Yeah, Autotech is the most unstable area. 2nd glitch looks similar to sewer bug reported by some people - best way is to keep distance from the bucket. For the last one, this glitch happens when Tex is in Movement mode. Switching to Interactive mode before cutscene seems to work. Maybe movement screen size (bigger, without interface) causes the glitch?