Cannot update or install

Since the last update, I've had to uninstall Lavish/IS Toolbox. When I originally tried to update, a crash reporter gave me the same thing I'm getting now after re-install:

Software: Inner Space Kernel 1.19 Build 7217 (Mon Sep 25 14:21:53 2023)
Current time: Sun Oct 1 15:41:02 2023
Crash: 0x00007FFD1F26CF19: Exception 0xe06d7363 in module KERNELBASE.dll

And, I can't even launch the ISToolbox downloader .exe as it's not recognizing a file format.

Not a power user, so hopefully someone has an answer that doesn't make me sound too stupid.

Thanks.