Other Mac users have reported issues trying to use iCloud when exporting or synching their project to their card.
Your cards should be MS- DOS(FAT32). If they aren’t of this format, try to reformat.
Sometimes because of the latency of the data transfer between the BeatBuddy Manager (BBM) and iCloud, data could get corrupted. I’m not saying your is but to get you back up and running, here’s what I’d do:
Make sure you have a bbworkspace folder in your computer’s Document’s path
Insert the SD card that’s working in your computer SD slot reader
Use BBM File - Open Project and navigate to your SD card and select Open
Accept the prompt to save to your computer to your computer bbworkspace folder user_lib/Projects (but not to your iCloud path); press either Yes or No to accept future syncs (doesn’t matter since it doesn’t work anyway);
Your BBM should now have the project open in your computer bbworkspace folder;
Eject the SD card
Make sure your new card is not locked and insert; verify the format and that it’s empty
Try to export the file from your BBM from your computer BBW folder to your card;
If this works, and you want to backup your project to iCloud, delete the project folder that’s on the iCloud and then copy your project folder from your computer to the iCloud.
I think, but I’m not certain that you can go to System Preferences/iCloud/Desktop & Documents Folder and uncheck your BBW folder and you should probably do so.
If this doesn’t work, contact me via PM