Welp…I was gonna change each file one by one (I tried it with various “search and replace” programs but none could deal with the .vstpreset estension). But decided to just move the impulse responses over to to the old place. Not very neat but oh well… would be nice is this could be added later. Kind of like Kontakt’s or Omnisphere’s method where you only have to find it once if you move where the library is kept.
I guess you don’t really think about these things until you have to deal with them. For those that use a lot of presets this will (eventually) be a real PITA for them unless they keep the exact structure on their new system.