I could be wrong but I don't think this is a compatibility issue between older dynamic clothing and the new Poser cloth. I think Poser cloth just doesn't work correctly.

Here's a basic test I made of a cloth draping over a ball and stairs :/ as you can see the cloth is basically ignoring the highres ball and slipping straight through.

 

Even though the cloth is draping over the stairs its definitely not how it should look. It's as if the the bullet system spawns a collision object for the simulation but it's so low resolution that the cloth either passes the collision object or if it does "drape" its completely ignoring the original shape.

There doesn't seem to be any settings to change the resolution of the collision object? 

Trying to use the glue function doesn't exactly fix it either.

 

Collisions seem to be a problem which makes the cloth system reliant on the glue function.

Left image above is glue turned off on the left and right thigh with collisions on. 

Right image above is with glue turned on on all parts with collisions on. It helps a bit with poke through but completely destroys the actual draping of the cloth which is the whole point.

I do appreciate Bondware trying to implement a new cloth system (I'm all for change for the better) but did anyone actually test this out? surely a cloth and ball simulation should work lol