Only one track! Ok - i (sluggishly) understand -You have your musicians piano-part ALONE, with no other instruments, only the piano, and that track does have velocity data, for the piano.
These velocity data are lost in the import of the MIDI-file, that was created on a pro-MIDI-kb.
-But then i want to get back to what you wrote :
So neither Anvil, FLs or indeed LMMS can import the velocity-data?I think anvil handles the MIDI exactly like FL Studio :/
I clicked on "Properties" on several notes in the midi and they all showed up "Note Volume: 100"
That could indicate, that your file has an 'odd' structure, something speciel for the pro-MIDI-kb..
What i would do, in your case, is to ask your musician if his MIDI-kb can export in one of the standards for midi
MIDI0 is the simplest, but im not sure it has velocity data.... 8|
I believe Anvil uses MIDI2 as standard export, but that you can find in Anvil documentation.
I will do some import experiment with midi exported from Anvil, to precisely get an understanding of the capacity for LMMS to import velocity. That must be perfect!