Hey guys, sorry for the delay. I only occasionally get notifications for this thread (I don’t know why) so if you need my attention please PM me or quote one of my posts 
Then I get an immediate notification!
The build has been updated in the first post, you can grab the latest from there. I honestly didn’t even know 4.15 had released, so cool new fun things for me to work with too! Sweet!
As for a Marketplace version, that’s up in the air at the moment. I am working on some projects for the marketplace to be sold (not iTween stuff, that remains free) and I may put the plugin on the marketplace after I learn how the process works, but there’s no guarantee of that at the moment. For now the best place to get it is from this thread and as long as I am working with UE4 I will keep the plugin compiled and updated for newer engine versions. And of course, source is available if you can’t wait for my ***