Virus Control VST Plugin Win/Mac incompatibility

Backround: We're working on PCs and Macs in different studios using Cubase 9.5, and are always moving Cubase projects between those workstations. Therefore we always keeps those systems in sync with regards to available VST plugins and versions.

Last week, I had worked on a project and created new sounds on the Virus TI at home on my MacBook Pro. Since I hadn't already printed those new Virus tracks to audio, and the Virus Control plugin is finally at the same version for Win and Mac, we wanted to try setting up the Virus TI in the studio and play the new tracks directly from within the Cubase project.

After installing the latest VC software, updating the Desktop Virus TI, and two Windows crashes, everthing seemed fine and started up.

Unfortunately, Cubase was unable to find the plugin named "VirusTI" used in the Cubase project as created on the Mac. It seems that a different ID is used to identify the VST plugins for Mac and Windows. This is a very unfortunate situation and severely hampers the cross-platform compatibility.

We've never had this problem before with any other of the many VST plugins we use (Steinberg and the whole NI and Slate Digital suites).

Is there a workaround?

Nobody transferring their Cubase projects between Mac and Win platforms?

Yes, identical SW version installed and therefore also the same Firmware.

Access Support answered me that I should try using the "Cubase Cross Platform Converter" available from the downloads page under Product "Virus TI Series" Category "Miscellaneous Files". The application is only available for Windows, so if you're using a Mac working on a Cubase project last changed on Windows you're out of luck.

Anyway, I wonder why the Virus plugin needs such a cumbersome workaround while all other plugins work just fine. Would be interesting to know whether Ableton Live projects can be transferred without conversion.

Yesterday, we tried the Cubase Cross Platform Converter.

And indeed, after converting the Cubase project file from Mac to Win, the Virus Control VST3 plugin was properly loaded.

Naturally, I was curious what the Converter actually changed in the cpr file. A binary diff revealed that a value which looked like an ID or GUID was changed throughout the document. When doing a conversion back from Win to Mac, the value was changed back. So I wondered what this could be, and a Google search for "vst3 plugin ID" dug up a couple of interesting bits. One of them pretty much explaining the basic problem of the situation:

VST3 Plug-In ID Changes on Mac

So, the VST3 version of the VC plugin for Mac and Win use a different GUID. Which is an incredibly unfortunate mistake that could be fixed in the plugin, but would require either all Mac users or all Win users to convert all their projects.