Your English is pretty good
Just to check: when you load an "embedded" 32-bit plug-in in Reaper 64-bit and scroll the mouse wheel over one of the plug-ins knobs, the preset list scrolls rather than the plug-in's knob itself.
What happens if you turn off the embedding for the plug-in?
I think that this is an "embedding" problem. The mouse-wheel change is not getting to the plug-in.
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If I use ST3 (a 64-bit plug-in) in Reaper 32-bit and embed it I get a similar issue (and some graphics glitches); if i disable the embedding that it works as expected.