sar_startdemos Crashes at Certain Maps

if one play a fullgame demo using sar_startdemos from the beginning to end, the game will crash out after nuero sabo (or at the start of core). if one remove some early demo and start from neuro sabo, the game will crash again at the end of finale 3 (or at the start of f4).

this behavior is seen by me and other runners multiple times so i'm sure it's a common issue.

crash report in Portal2/crash_reports/ says:

SAR 1.13.13 (Built 06:46:10 Feb 28 2025)
Segmentation fault caused by address 0x00636974
	(+0x2726f6e0) [0x00636974]
	(+0x0) [0x5672f56b]
	(+0x0) [0x567b37e5]
	(+0x0) [0x567b3bb7]
	(+0x0) [0x568b0963]
	(+0x0) [0x567aab1a]
	(+0x0) [0x5685601c]
	(+0x0) [0x568583f9]
	(+0x0) [0x56858773]
	(+0x0) [0x5686736b]
	(+0x0) [0x568674ba]
	(+0x0) [0x56867554]
	C:\Program Files (x86)\Steam\steamapps\common\Portal 2\portal2.exe(F+0x568ba00d) [0x568ba00d]
	(+0x0) [0x5291b51d]
	C:\Program Files (x86)\Steam\steamapps\common\Portal 2\portal2.exe(F+0x568b8df0) [0x568b8df0]
	C:\Program Files (x86)\Steam\steamapps\common\Portal 2\portal2.exe(F+0x568b8f0f) [0x568b8f0f]
	C:\Program Files (x86)\Steam\steamapps\common\Portal 2\portal2.exe(F+0x568b995e) [0x568b995e]
	C:\Program Files (x86)\Steam\steamapps\common\Portal 2\portal2.exe(LauncherMain+0x66df90e0) [0x66df90e0]
	(+0x0) [0x002211dc]
	(+0x0) [0x0022177e]
	C:\Program Files (x86)\Steam\steamapps\common\Portal 2\portal2.exe(BaseThreadInitThunk+0x76bafcc9) [0x76bafcc9]
	C:\Program Files (x86)\Steam\steamapps\common\Portal 2\portal2.exe(RtlGetAppContainerNamedObjectPath+0x77c07c6e) [0x77c07c6e]
	C:\Program Files (x86)\Steam\steamapps\common\Portal 2\portal2.exe(RtlGetAppContainerNamedObjectPath+0x77c07c3e) [0x77c07c3e]

Start by reproducing the crash with sar_startdemos through the reported transitions: after Neuro Sabo or at Core, and at the end of Finale 3 or start of F4. Inspect the crash report in Portal2/crash_reports/ and use the reported segmentation fault to identify the relevant code path; done means fullgame demos no longer crash at these maps.