[Crash] 'WIN32 Exception: Access Violation' on track edit.

[FearJudge]

Hi.

Made a level in Map Editor, works pretty nice but now when I try to edit it after a relaunch, it just crashes on random. Seems to be when I try to do anything that influences the shadows. (Adding blocks, removing blocks), though sometimes just moving the camera crashes to desktop.

The CrashLogs catch the following error:
Win32 Exception : Access violation
=>Occured at address 0x00BFA610
The thread tried to read from the invalid address (data) 0x83EC8BE9
eax=0x0019F7DC ebx=0x5F94BB00 ecx=0x83EC8B55 edx=0x83EC8B55
edi=0x6ECA8184 esi=0x00000000 ebp=0x0019F7FC esp=0x0019F798 eip=0x00BFA610
@ [nofiber] / t=(769239, 279609)
Called from address 0x009EAE98
Called from address 0x009EAE98
Called from address 0x00B8B9DE
Called from address 0x00CFEB2D
End of stack...

I'm running a 64-Bit Windows 10, Nvidia GeForce GT 820M and Intel i5. (Not ideal, I know)

Things that might be of interest (from crash log):
[Sys] Windows version = 8 [...]
[Sys] Os = Windows 10 Home(17134.rs4_release.180410-1804) 64b [...]

[Sys] ---- GlobalMemoryStatus(Startup) ----
[Sys] MemoryLoad = 43%
[...]
[Sys] ---- GlobalMemoryStatus(Now) ----
[Sys] MemoryLoad = 55%

If anyone has some idea or trick that I could try, let me know. I'm not really sure what could be the issue, every other level and feature seems to run fine so I'm almost certain it's due to my level having heavy pre-rendered shadows (via fast) when I saved it.
All suggestions and ideas welcome, if you need additional info, let me know.

[If it's of relevance the level in question uses solid blocks to make the level 'dark' by blocking direct light, and uses neon and seperate lighting to allow the player to see. Hence the term 'heavy' shadows.]