I'm not certain this will work, but we did this for stl files and it worked pretty well. To add a preview handler to EPDM you just need to add a registry key with the file extension and tell it what viewer to use. So go into the registry on a machine with EPDM, add a key under HKEY_LOCAL_MACHINE\SOFTWARE\SolidWorks\Applications\PDMWorks Enterprise\FileFormats that matches the file extension you are working with, then add a string value under that key named 4 and put in the dll that previews the file as the value, if you can open the file in eDrawings then use SolidWorksPlugin.dll, but you may need to play around with some of the others if that doesn't work, possibly AutoVuePlugin.dll
Do the same thing under HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\SolidWorks\Applications\PDMWorks Enterprise\FileFormats
How can a user utilise the different drawing/document viewing/editing applications used by PDMWorks® Enterprise?
Answer:
When working with PDMWorks Enterprise and Microsoft® Windows® there are three types of application viewers/editors that may be configured.
1) PDMWorks Enterprise Pane This is the most difficult viewer to configure. See solution S-014109, “Is it possible to use a third-party viewer in the preview area of the PDMWorks® Enterprise Explorer interface for viewing file types not supported by the existing viewer?”. Note, with reference to this solution, if DWG TrueView is installed then setting the .dwg registry key to “dwgplugin.dll” will use DWG TrueView as the embedded viewer, setting the registry value to “SolidWorksPlugin.dll” will use the eDrawings embedded viewer (requires a reboot to load registry changes).
2) Document Viewers This is the viewer that is launched when clicking on “View” on the history dialog or if right mouse button clicking a file in PDMWorks Enterprise and selecting View/Markup. See solution S-013165, “What is the procedure for setting up a third-party viewer for viewing different file types in PDMWorks® Enterprise?” This is a relatively easy way to modify and does not require a system reboot.
3) Windows File Associations The last type of viewer/editor is the application that is launched when right mouse button clicking on the file and select Open or Edit, either from within a file vault view or outside. These are defined in Microsoft Windows and are outside the control of PDMWorks Enterprise. File extensions are usually registered by an application in Microsoft Windows when the application is installed. To edit these, select Tools, Folder Options, File Types, select the appropriate file extension and click either Change or Advanced to change the associated application or the commands to perform. Note the File Types tab is not visible inside a PDMWorks Enterprise vault view.