You aren't the only one this is happening to, I've been having the same problem starting at right about the same time you described, and it's made LaunchBox unusable for me, which is unfortunate, as I was impressed enough to seriously consider pulling the trigger on purchasing Premium when this broke.
I'm no expert at reading log files, but from what I've been able to discern, the only obvious difference between a log from a run where I didn't edit anything (and thus didn't freeze) and a run where I did, triggering the freeze, is an exception on the "Visited Links" file in Launchbox / Metadata / Temp:
2020-04-12 06:19:06 PM FIRST CHANCE EXCEPTION: The process cannot access the file 'Visited Links' because it is being used by another process.
at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)
2020-04-12 06:19:06 PM FIRST CHANCE EXCEPTION: The process cannot access the file 'Visited Links' because it is being used by another process.
at System.IO.Directory.DeleteHelper(String fullPath, String userPath, Boolean recursive, Boolean throwOnTopLevelDirectoryNotFound, WIN32_FIND_DATA& data)
2020-04-12 06:19:06 PM EXCEPTION IGNORED: The process cannot access the file 'Visited Links' because it is being used by another process.
at System.IO.Directory.DeleteHelper(String fullPath, String userPath, Boolean recursive, Boolean throwOnTopLevelDirectoryNotFound, WIN32_FIND_DATA& data)
Something involving this file seems to be the problem - maybe a dev is reading this and can weigh in on what might be going on. The file is still in the Temp folder after LB shuts down, unlike the multitude of other files/folders created in Temp during runtime, which do get deleted when LB closes.
LB is running from my Documents folder, which has full read/write privileges, and the problem occurs whether running under my own user account (which has admin rights on the computer) or "Run as administrator".