No problem with that, this stuff is complicated.

I do have both NGM products, yes. I would do the morphs with Silo, not Hexagon, but just that's no big difference. I don't need Morph Loader since I have Poser.

The tutorial is for making a morph for an unmorphed figure. If you export a shape which is already morphed, your new morph will have the old one too. 

After loading your morph, try to set all other morphs to zero, and apply your new morph only to the morphed body part. So, if you use a full body morph, you would go to the body part you created your own morph and set the respective body morph to the same negative value as you have set the full body morph.

A ship in port is safe; but that is not what ships are built for.
Sail out to sea and do new things.
-"Amazing Grace" Hopper

Avatar image of me done by Chidori.