Here is what they are saying,

"...unlike the 64/32 bridge that is built into Reaper 64 for VST/VSTi, there's no bit-bridge for directx plugins - reaper x64 can only load 64 bit directx plugs, and since it's a dead format for audio fx finding any of those isn't very likely".

So why my Dxi Isotope Ozone 3, is working I don't know, since due to its age I assume it is a 32 bit, but I am not complaining. However, this may explain why no Forte Dxi. Not a big problem for me since 95% of my Reaper projects as pure audio and the little bit of Midi is easily handled by many other virual instruments (VSTi, such as the free EWQL Symphonic and Kore Player).

BIAB – 2025, Reaper (current), i7-12700F Processor, 32GB DDR4-3200MHz RAM, 1TB WD Black NVMe SSD, 2TB WDC Blue SSD, 1TB WD Blue, 2 TB SK NVMe, 6 TB External, Motu Audio Express 6x6