You mean, portrait...

All these people always moaning about not having portrait mode and then when they get it, they complain.

Well as i mentioned in the release note, i changed the mame.ini to enable autorotate for games that are vertical. It creates a big enough problem for controls that i will change it back for the next release.

As for the slowdown, that's interesting. Did you try any of the ROMs from the wiki and see if your results are comparable?