*LOL, no kidding! I don't really know what that is exactly...something about triangles.*Yes, but I gave a pretty good work around that really isn't that big of a deal actually.
It only took me a couple of minutes to do the whole thing.

Export your object as a 3DS object.
Close out what is currently loaded.
Import that same 3DS object that you just exported.
Export that right back out as a OBJ object.
And there ya go, an object that is triangulated and in the format that Ivy Gen wants, OBJ format.

Just use the settings I posted above :)

Update Note:
And yep, by Flipping the UVs on Importing the Ivy OBJ into Poser, 
that makes the leafs all the correct way and looks fine! :)
And in a few minutes here I'll have my very first Poser/Ivy Gen scene :)

............md :)