I Didn’t understand what you were trying to achieve. Direct publishing isn’t officially supported but having said that I did a small test and seems to be working.
Test the following, in the GWP Administrator create a Raster connection with the physical path to your hmr files. Apply and restart the services, a new application should be created in IIS with the same name given to the Raster connection.
Now open your IE browser and use an url similar to http://localhost/RasterConnectionName/rastername.hmr or http://websitename/RasterConnectionName/rastername.hmr
Regards,
Carlos