I have a bunch of old topics bookmarked and after going through a few of them some are redirecting to this one:

https://forum.videohelp.com/threads/316418-VirtualDub-Remove-Region-plug-in-problem

Doesn't work:
Code:
https://www.videohelp.com/forum/viewtopic.php?t=214273&highlight=
Works:
Code:
https://www.videohelp.com/forum/viewtopic.php?t=214273
I haven't checked any other parameters.