It doesn't  seem to. The last version I confirmed it worked with was 7. Is there an alternative?

The Morph Manager I know (and host) is a stand-alone program that doesn't work "in" anything.

In what way is it not working? I tried opening a Miki 4 dress in Morph Manager 4 and had no trouble, but there may be some later Poser features that choke it. It hasn't been updated since just after the last ice age. ;)

I'm with EnglishBob, I haven't seen any problems yet.

I meant does it work with files created in Poser 9. Must check to see if I'm using MM4.

You are correct about the ice age.

The problem could have been I was working with messed up files saved with "use external binary jazz" checked.

I'll try again using it to delete morphs I don't need. A real convenient and needed feature of MM.

External binary morph creates a separate PMD file which will contain all your morph information.  That will keep the size overhead on your models to a minimum.  However, PMD files are prone to corruptions and aggravations.

Quote - The problem could have been I was working with messed up files saved with "use external binary jazz" checked.

That's the problem! MM4 won't work with a cr2 saved with the external morph targets option, because amongst other possible reasons, there are no morph deltas in the cr2 (the deltas are the morph).

In the Poser Edit menu > General Preferences > Misc tab, turn off both 'Use file compression' and 'Use external binary morph targets',  then resave the figure. MM4 should have no problems with the new cr2.