I took a pass recently at integrating the version a user posted on GitHub that worked against 4.11 (), which also included arbitrary gravity for the engine in general.
I had to fix a number of issues along the way, including some code that still had hardcoded Z=down assumptions, but overall it looked good. I did get it working but there is a ways to go, in terms of testing, cleanup, and performance. Some backwards compatibility also needs to be addressed.
I’m not sure if it will make the next release, it’s possible it could where Z=up behavior is unchanged and supported, and the other orientations are working but still considered rough and “experimental”.
-Zak