This seems to be the big topic floating around each section of the forum. This
thread in the ARP2600 forum seems to have the most discussion.
The legacy factory & user presets won't be compatible with the new plugins versions because the programmers rebuilt every plugin's architecture, essentially to standardize their preset format. Some of the first plugins were a bit old and I guess were all programmed a bit differently. Anyway, they have decided to develop a preset converter in order to make patches from the legacy versions compatible with the new plugins and hopefully it will be available soon.