Did you try it with latest v184.108.40.2068 ?
Is there a link where you can download such file ?
Email the link to: lionel(at)vso-software.fr
Let him know this file failed with v220.127.116.118
VSO will investigate, and maybe support this format in the next version.
Seems this format is
supported by ConvertXtoDVD, but you cannot select them as an input file, unless you select (*.*) so see them as a supported file.
There's an open request (#1125) with VSO already to get .m4v listed as a valid extension.
.m4v is format from itunes video which is supported in convertxtodvd, but until added to list of supported files one must first change browser selection to all files (*.*) in order to add it for conversion . . . . see screen shot attached