i actually dont really think too much about the version because i assume whoevere uploaded it is probably using the same type of mugen as me judging by the screenshots and videos.
unless it is a very old video or screenpack i dont recognise, i dont really have compatibility probelems.
only thing i do notice is some creators only make directx content not opengl?

With the Ikemen Go engine gaining popularity more, I see that it will be less important what mugen version a creation is because Ikemen Go was based on an older build of Mugen I heard and not 1.1 anyway. That is to say, if it does eventually replace mugen