The Posers internal SubD is not taken into acount in the fitting room.
It reverts back to traditional, but it is better to avoid this, and go in the fitting room In Poser traditional with the clothing and figure anyway.

 

The only thing you can do is change the mesh density of the clothing outside of Poser.
Take the clothing object into Hexagon, Blender or whatever you prefer, and SubD untill it +/- maches the poly density of the figure.
Then use that object file in the fitting room.

As you want this clothing to fit your figure use;

• tranfer bones as required => Extra remark for sleeves. => Include all the arm and hand bones, exclude only the fingers.
• transfer morphs as required.
• autogroup, and let Poser build the groups from the underlying figure
• Zero

Click create

Poser 1, 2, 3, 4, 5, 7, P8 and PPro2010, P9 and PP2012, P10 and PP2014 Game Dev
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