Rotated tiles exported from Tiled work visually, but I noticed the collisions are not rotated. Am I doing something wrong, or is this not supported currently?
The good news is you can look at the code that handles collision shape generation of tiles and even fix it yourself now. 
I’m not yet familiar enough with the source to point to the right spot.
That’s true!
I very much doubt it! 
Never know until you try.
And then try again. And again. Until you learn enough to fix it. 
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