Hi,
I can see in FL that when I use the fader assigned to CC1 the DAW detects midi info, but it's not detecting any midi info when I use the faders assigned to other CC channels.
How do you see what FL Studio detect?
I mapped the CC1 to a fader and that successfully worked.
Is this your Spitfire product:
https://www.spitfireaudio.com/shop/a-z/spitfire-studio-strings/ ?
If so, then please read "5. EXPRESSION CONTROLS". It look like, they wan't you to use certain midi cc's for certain expressions.
But please keep in mind, that you probably have other ways to control the application in your DAW.
In case FL Studio actually does filter out midi cc's, then i think it's about the way you have set up and perhaps mapped your controller in FL Studio. Please be sure you have done everything correct.
I don't use FL Studio, so i can't help you with that.
FYI: Usually Absolute modes for encoders work. When using Relative modes the choosen relative mode need to be supported to work.
At this point based on the things you choose to provide, then i don't see anything, that can't be about the way you do things.
It can be very important to test and inform correct. I have to read between the lines as it is. I need informations to tell more.
As you mention you think FL Studio as the problem, then it look like, you have'nt testet midi learn with a standalone application outside FL Studio. It could be the old Massive (Not Massive X) from NI Komplete, as it sound like you have Komplete. You can also try with Arturia applications outside your DAW.
If things work outside your DAW, then you know there is something to solve in Fl Studio.
Just in case: Remember to move a control like a fader/ slider that you wish to assign a parameter fully in both directions. That sometimes is needed to assign a control. It sound like you have'nt tried to assign controls before.