Tell me what release package you are referring to? I've been out of touch so long, I don't know these things I've been talking to Dragon32 and I think I'll be able to get to work soon at the Sourceforge site. If the perl source to tes3cmd isn't included somewhere it should be, I'll look into it. Just let me know what you'd like to see.
I am definitely interested in making tes3cmd work well with OpenMW! One thing I am considering is to include a method of synchronizing load orders between your old Morrowind install and new OpenMW install. Or something like that. Might be able to help Mash work with OpenMW.