Kessler crash

[TURPX]

The game keeps crashing when meeting Kessler for the first time, any fix to this?

[Kritzburgh]

That crash is caused by changing the resolution to a custom widescreen resolution through the wolfconfig.cfg file. It's outdated advice that's been given for over a decade before RTCW had better solutions for modern resolutions. For a temporary fix, change the resolution back to something normal like 1024x768 (4:3) or below, and then the next level will load fine. You can then add back in your custom resolutions, but note that there are more end-level crash instances throughout the campaign.
Since you're mid-playthrough, it would be easier to download RealRTCW for a permanent and stable native resolution option since you can choose to start Chapter 2/Level 4 from the main menu of the mod. It's an excellent remaster, very faithful to the base game. The ioRTCW source port is another good solution as well if you want a 1:1 vanilla experience. You'll have to load into the level you're supposed to be on through a console command:
/spdevmap village1

Hope that helps. Links to both mods are listed below:
RealRTCW Mod on Steam
https://github.com/iortcw/iortcw/releases/tag/1.51c