You really do not need anything running in the background taking up more memory. Gyrator and Changescreen are completely unnecessary.
Use G Config to add ANY program to your landscape whitelist. Just run it, switch to or run the application you wish to auto rotate (Including Manila) and re-insert the stylus. There is even a version for phones without a stylus sensor.
No complex guessing at executables or which direction.
http://forum.xda-developers.com/showthread.php?t=487991