Shortly after attempting to do a conversion of LuaGame to OpenGL, I scrapped it. Nothing was quite working as it should have. I didn't (and still don't) have good experience yet with programming OpenGL, so that probably contributed to it. I may go back to it at a later date, but for now, OpenGL support is going to have to wait until SDL 2.0 (it'll be the backend).
While this may seem like bad news, it really isn't. I've managed to implement delta-based animation support (at least in the base library). No game currently uses it, but the option is there.
I have implemented not only on-the-fly rotation support, but also a new collision system that supports oriented bounding boxes. What this means is that basically rotation is trivial to use. For the user, rotating a sprite is exactly the same as not rotating it. From the aspect of performance, the rotation does have overhead, but it's not too great. The new collision code does use a little more resources, and does run a little slower, but it's worth it for the luxury of rotation. The old code is still available, so no worries.
For people that really want/need to do crazy things, there is preliminary support for intermediate surfaces. There's not yet the ability to do pixel-level manipulations on them (besides drawing single pixels to them), but any functions that could have supported them now do.
There you have it. I had to take a pretty long hiatus from development for personal reasons, but I've implemented almost everything that I had planned and more.
Side note: I switched hosting providers so I haven't gotten around to fixing my build script, so the builds currently on here are really old.