I'm able to use TT 2.x through the "File Types". Xlobby comes with default theatertek settings (for 1.5 I believe). You need to modify it and "enable" the checkbox. Here are my settings
Program:
C:\Program Files\TheaterTek\TheaterTek DVD 2.0\TheaterTek DVD.exe
Extensions:
ifo,iso,img,video_ts,tp
Command Line Switches:
/AP 2 /nosplash %playlist%
I added the tp to extensions b/c I use TT to playback myHD recordings. /AP AutoPlay (0-off, 1-On Insert, 2-On Startup, 3-Both). One of the main reasons for TT not working 'out of the box' in xlobby is Andrew changes the command line options on different versions/patches....ie once it was /path then /pl now nothing!
If you aren't using the very latest TT (2.2.1.12) then try /pl before %playlist%. Latest patch doesn't need /pl.