If you jump too high, you might trigger a map-boundary crash. Try reducing your jump height if using a slider trainer, or avoid jumping near the extreme edges of the map.
Check the Project I.G.I. section on ModDB for verified, virus-free community patches and trainers. Igi 1 High Jump Mod Download
: Drastically reduces the time needed to complete stealth missions by bypassing long paths guarded by patrols. If you jump too high, you might trigger a map-boundary crash