.PRT extension and multiple NX versions

http://nxway.blogspot.ca/2007/10/prt-extension-and-multiple-nx-versions.html

To open prt files with NX 7.5: 

Change HKEY_CLASSES_ROOTUGpartfileshellopencommand  to

"C:Program FilesUGSNX 7.5UGIIugs_router.exe"  -version=V25.5 -ug -use_file_dir  "%1"