If you are encountering errors with Poser Fusion shelf buttons in Maya such as "Error: No Selection, or the Currently Selected object is not linked to a Poser file", then
try the below steps and see if its helps.
First of all ensure that your POSER_LOCATION environment variable is set correctly. It should read something like "C:\Program Files\Smith Micro\Poser Pro".
Next, ensure that the PoserFusion plug-in is loaded in Maya. You can do this by going to
Window > Settings|Preferences > Plugin Manager and then checking the "MpzFile.mll" to be loaded state.
Once these two steps are done, you should be able import any Poser file into Maya. You should select the "Poser(*.*)" option in the file dialog while importing the Poser file.
Once the file import succeeds, now all your PoserFusion shelf
buttons start working correctly. Details on how to use these shelf buttons can be found in the
PoserFusion for Maya section starting on page 38 of the Poser Pro Reference Manual.pdf available in the Poser Pro application folder.