If you have the midi files with the drum parts, and you want the drum parts only for BB, sure, that’s simple to do. All you have to do is select just the drum track, and export it as a midi file. Or, if for some reason CAkewalk is given you difficulty in doing that, first make a copy of the midi file sand save your original somewhere safe. then open up the copy. Delete all of the tracks except for the drum track. Export or save the song with just this one track as a midi file. You can then go into BB Manager, Click on the “+ Song” button between any two tracks in a folder, or select New Folder, and then click on +Song.
This will then display:
Enter the song’s name and tempo. Select a drum set from the drop down. Then, if you click on the box with … in the Main Loop section, you will be given a browser window from which you can navigate to the midi file you just made. Click on it, and it will be added to the song. You can then play the midi file in BBM. When you are done, save the project, and then export the project to your SD card (or synchronize, if you can), and you file will be on the card and available for play in the BB.
Feel free to ask for help.
If your stuck, send me the midi file, and I’ll take a stab at it.