Backup your save files before trying any of these fixes! They are the plyslot*.dat files in your GTA2\player folder. Not all saves are compatible with all versions of the script files.
edit: GTA2 v11.44 fixes this bug in the exe file. If you have v11.44 then don’t install the below fix (unless you really want the cars that are supposed to be on trailers to not be on trailers).
GTA2 corrupt save game
GTA2 save game crash
GTA2 save game glitch
Not technically a bug with the saved game but I put those keywords here, so people can find this page.
If you save the game after attempting any trailer kill frenzy (these are cars on top of trailers that can only be taken down by certain cranes), GTA2 will crash when you load the save since it tries to put a car that no longer exists on top of a trailer. I fixed this bug on level 3 (Industrial) by adding a check to the .mis file, to see if the car exists before trying to put it on a trailer.
I can’t do that for level 2 since the level 2 .mis file was never released but I was able to patch the level 2 ste.SCR (Residential) with a hex editor and remove the PUT_CAR_ON_TRAILER commands completely. This will stop the game from crashing when you load the saved game. The car won’t be on the trailer, so you can just start the kill frenzy without taking the trailer to the crane.

Download: gta2-trailer-kill-frenzy-fix.7z – 76KB
Extract the files to your GTA2\data folder
This is the code I added to bil.mis
IF ( NOT ( IS_CAR_CRUSHED ( KF_3_car ) ) )
PUT_CAR_ON_TRAILER ( KF_3_car , KF_3_trailer_1 )
ENDIF
IF ( NOT ( IS_CAR_CRUSHED ( KF_4_car ) ) )
PUT_CAR_ON_TRAILER ( KF_4_car , KF_4_trailer_1 )
ENDIF
IF ( NOT ( IS_CAR_CRUSHED ( KF_5_car ) ) )
PUT_CAR_ON_TRAILER ( KF_5_car , KF_5_trailer_1 )
ENDIF
—————————————-
These are the bytes I changed in ste.SCR to null out the PUT_CAR_ON_TRAILER code
Comparing files steFIXED.SCR and steORIGINAL.SCR
000092FE: 00 3C
000092FF: 00 01
00009304: 00 FF
00009305: 00 01
00009306: 00 02
00009307: 00 02
0000930A: 00 3C
0000930B: 00 01
00009311: 00 02
00009312: 00 03
00009313: 00 02
00009316: 00 3C
00009317: 00 01
0000931C: 00 01
0000931D: 00 02
0000931E: 00 04
0000931F: 00 02