
A few plugins see their 64-bit and 32-bit plugins as separate products. I was sad to lose it and went as far as buying SampleTank 3 so I could import and continue to use the old libraries. Of course, a few had no 64-bit counterparts, but fortunately only one of my 32-bit plugins (SampleTank 2.5) failed in the 64-bit environment.

For the customer-friendly vendors (Valhalla, Melda, FabFilter, Voxengo) that was painless. That meant having to download 64-bit versions of existing plugins. Like you, I was also migrating to 64 bits. For example, Meldaproduction makes it very easy: just copy over the license files. How much of a pain that is varies a lot from vendor to vendor. But many, perhaps most, will have to be re-authorized. After a re-scan, many of them will just work. You don't have to worry about overwriting the 64-bit versions of SONAR-bundled plugins, because they're in another location. You can start by simply copying your previous VSTPlugins folder to the laptop. I'll relate some of the challenges I experienced. It was not an entirely pleasant experience.

I just went through this earlier this year.
