First of all:

Special thanx to all of you maintaining an caring for this great piece of art-addon. loved it for years, still do!

Question:
Would I still be able to find a version compatible to Game-Version 3.3.5 or slightly older?

Sorry for the bother and keep up the work you do!

Kabulla

This will not be possible as this addon didn't exist until Legion 7.0+, and there are no old versions of the addon compatible with the outdated API. I do not have plans for trying to add support for private servers. Sorry.