wrt 1/4, is it actually broken? Do the relevant machines report support for nv12 via CheckFormatSupport()?
From 4/4:
ok(!!content || !!content2 || !!copy_source, "Failed to allocate memory.\n");
That should be &&, right? (Admittedly checking the result of malloc() using ok() is a bit odd in the first place, but eh, whatever.)