It's pretty easy already: I run 9.21, 9.90, and Phy5. I don't even have to move or copy the VP folder. Although, for me, I tend to keep only one version of a table. Here's what I did: In the Setting Wizard - Other Systems screen -define a new system for Virtual Pinball. Call it anything you want, "Virtual Pinball - New Physics" maybe. Enable it. Same Working Path, same Table Path, same Parameters as your usual Visual Pinball settings. The executable will be PhysMod5.exe or whatever. Go the PinballX/Databases folder. Create a copy of the Visual Pinball folder. Rename the folder to "Virtual Pinball - New Physics". Inside the folder, rename the xml file to "Virtual Pinball - New Physics". Edit the file in Notepad or whatever. Cut out all table listings where you do not have a PhysMod table. Save the file. Go to the Visual Pinball folder. Edit the Visual Pinball xml file. Cut out any table listings where you are using the PhysMod version instead. Save the File. Now go to the PinballX/Media folder. Copy all of the contents of the Visual Pinball folder to a new folder and call it "Visual Pinball - New Physics". It doesn't matter about having duplicate media files unless you simply need the disc space. It will work. That's it.