I'm just posting to agree with RobynsVeil, and add that it will probably be better to group your item in Blender where it's easier to control  what goes where.  Dresses need special treatment for conforming.  It sounds like this might be a hard to make dynamic as you've made it.

Conforming clothing can have separate meshes that act as one.  Dynamic needs either to be a single mesh (easiest solution) or to use the various special groups like soft decorated, hard decorated, constrained, and choreographed.