I guess there is no way to modify the asnrating tag outside of ejukebox correct? I would like to take an existing playlist and batch edit all the entries and set the rating to 80. Has anyone been successful doing this?

Yes I think it's correct.. Unfortunately I don't think it exists a tag editor which can edit such non-standard tags. At least I don't know one!

Darn...

Well, there is Mp3/Tag Studio which can edit the eJukebox asnrating tags, but manually.. I've tried to change a rating and that works: eJukebox see the change if you reload the file tags!
But I don't think that Mp3/Tag Studio can create the "asnrating" tag if it doesn't already exist? It's a shame because this program can record macros!