When you convert your movie from .avi to .m2v, the movie's framerate changes. I found that if you have a .srt that works with the .avi movie, you can make the subs work with the .m2v by changing the framerate of the subtitles. When you go to Subtitle workshop to convert the .srt file into .stl for DVDMaestro, or whatever other format, you should also change the FPS that is on the left hand side of Subtitle Workshop. The FPS should be changed to 24, and the Input FPS is always going to be 23,976; 23,978; or 23,981. Once you do those changes, save the .srt file as a .stl file for DVDMaestro.