I went from Opus v1.1 to 1.3.4 today, and now when I open all my old project files it says Opus is missing. I can insert the new synth, but all the old synth instances are broken and I can't get my settings out of them or change the plugin to the new one. I tried a System Restore but a problem with my company's OneDrive account means System Restore is broken and won't work. I cannot find anywhere to downgrade Opus back to v1.1.
What do I do to salvage my projects?