when you it doesn’t work in 64 bit mode, you mean the audio engine, or the project (64 floating point). because the first is known bug, in an older version of cubase.
i acquired spectralayers pro 6 quite recently, so i can’t answer all questions on a level that you want.
but it seems you want a kind of AI. it is a chirurgical tool, it recquieres when want to select something, also setting of the resolution (the FFT resolution), for example.
i don’t know if rx7 advanced (or standard can do it all), can do this stuff.
me thinks, you can do it in spectralayers, but it recquires practice. i agree the manual is brief, most examples are poor. although some are great, on youtube.
which version did you demo? elements or pro?
for sounddesign i use it the most, it works quite well. even with my very strange samples. to seperate instruments, or what you say in the first sentence, it can be done. look at the thread, with the youtube video’s.
there is room for improvement, more feedback. but the possibilties that the pro version gives, are already great.
slow? i didn’t notice that. 16 bars takes minutes? i have tested a “stem”, more than minute long, processing took seconds. within cubase pro 10.5.12.
but maybe spectralayers isn’t your thing. rx7 isn’t my thing, for example. it comes to personal wishes.