The BCR does have a channel setting (omni or 1 to 16) , but that is only used for changing BC presets.
I'm not sure what you want to do with Note messages.
When you program a BCR's control to output Note messages, you have to include the channel for that note.
Looking at the PG_300 code in the sysex file, most of the controls send out PG300 sysex as you would expect.
There isn't anything programmed to output Note data.
Encoder 15 changes the Patch on channel 7
Encoder 16 is a volume control using CC7 on channel 7
Bizarrely....
Encoders 20 to 32 output CC 20 to CC 32 on channel 1
Buttons 1 to 6 output CC 33 to CC 38 on channel 1
Buttons 9 to 32 output CC 41 to CC 64 on channel 1
Button 32 , 49, 57, 58 , 59 have no message
Sadly it then goes on to store the preset in memory 1 and erase all the other presets in the BC.
I believe this was an early problem with Mark's editor.
You can download Mark's editor and load the PG300 sysex file and change it.
Or perhaps if you tell me what you want to do I can help.
You can always write in Spanish(?) and use Google Translate if that is easier
All the best
Royce