It is posible to make a MAT pose work on an unparented prop, but there are a couple of restrictions. First restriction, there must be some figire in the scene, even though the prop does not need to be parented to it. Second restriction, a MAT pose for "MyProp_1" will not work on "MyProp_2", Poser increments the prop number each time you add another instance of the same prop to the scene, so you have to be aware of this li mitation.

The MAT pose file needs to be in uncompressed 'pz2' format so you can edit it in a text editror. Lets take this simple example that applies the default ground texture to a Poser box primitive:

{

version
 {
 number 4.01
 }

prop box_1
 {
 material Preview
  {
  textureMap "GetStringRes(1029,7)"
  }
 }

figure
 {
 }
}

The way to make this work on an unparented prop is to edit the line "prop box_1" to read "actor box_1":

{

version
 {
 number 4.01
 }

actor box_1
 {
 material Preview
  {
  textureMap "GetStringRes(1029,7)"
  }
 }

figure
 {
 }
}

Thats it, it's that simple! But remember, there must be a figure in the document before any pose file will work, and a pose for "box_1" will not work on "box_2". This method works in all  versions of Poser.

There are also a couple of workrounds that can help in applying poses to props. You could load a figure without any geogetry then parent your prop(s) to that, if you wish the figure can then be saved back to a figures pallet with the prop attached, so that next time you load it you can imediatly apply a MAT pose. "MinFig" from the Free Stuff can be used to this end.

Another workround is to use "actor $CURRENT" in the pz2, this will allow the pose to be applied to the currently selected prop (or body-part) irrespective of its name (but you still need to have a figure pressent in the document).   "actor $CURRENT" only works in P5 and up.