GameSave Manager

Program locking up when "Processing..."Train Simulator 2022" on steam install. I uninstalled Train Simulator 2022 and the scan completes fine. Re-installed it and it locks up again. JFYI

It's likely trying to process a large number of files. Use the /ignore commandline switch to opt to skip the record you're having trouble with.
For example:

I updated from version 3.1.455.0 to 3.1.507.0 , and it used to process Train Simulator 2022 a lot quicker, the thing that used to take the longest was processing all the Steam Screenshots, but now scanning/processing all files takes over an hour. (most of it on Train Simulator 2022)

An hour? Jeez.
You could better define what to backup via Custom GameSave Entries. Simply use the same title as the "official" one and you can modify it, perhaps even optimise it a little by being a little more explicit in where to look?
Failing that, you could try the 4x Alpha builds. They're far quicker at scanning and the core "backup and restore" functionality appears stable. Find it on our Discord server.

Same problem, I had to set it to ignore Train Simulator 2022 as well. How does this work? Does the Train Simulator 2022 database entry just need better refinement as to what folder / files it checks for?

Version: 3.1.517.0
Released: 5th October 2022
Database: 9.2023-03-12_01

The issue is caused by one of two things: either a large file count or very large files (typically the former).
A more refined ruleset could potentially help, depending on the save structure (i.e the issue is caused by 'junk' data).