The program has crashed about 6 times. All I'm trying to do after making timing marks is place effects in the timing slots. I was able to get about 13 seconds done over a period of a few days before it started crashing. I remember trying to get some effects to appear in the preview. Some would not appear. I was repositioning the timing marks and it crashed. I reopened the program, put the timing marks back in. But before it crashed, I decided to do a save so that I wouldn't loose those. When I clicked on save it crashed.
I reopened it again. The timing marks got saved.
I continued to place effects in the timing marks. One effect, the curtain, I couldn't get it to appear in the preview, so decided to delete the effect. When I did delete it, it crashed.