I've been working with the "SEGA Dreamcast Movie Creator" tool posted by "SWAT", in an attempt to re-encode SFD movie files, and I've been running into a few issues I wanted to troubleshoot.
Since the tool uses MPEG-1 format, I have a test file ready, originally converted from a 640x480 avi file.:
Test Video: MPEG1 Video 352x240 (880:657) 29.97fps 1152kbps
When attempting to encode into sfd, or m1v for testing, I get the following error message:

Does anyone know where I am going wrong? Or have any troubleshooting tips I can try to isolate the cause of the issue?
Many thanks!