Actually, if you want a downgrade CMT to PR1.1.1 level you can try just use a parameter "--cmt-no-verify" during flashing PR1.1.1 PR1.1.1 for USA has all CMT files, you may need only suppress verification. International misses something (file size is significantly less). But I didn't test it. Also, somebody said that reflash to previous (PR1.1) version helps in downgrading CMT.