I've seen this error myself (in post 1) and i believe that in some cases its caused if the OSX drive that your running mutlitbeast on is not the drive that contains the EFI partition with clover on it.
Because i run multiple OS's (4 of them) for me it makes sense to have each OS on its own SSD drive. And to make it easy for me to manage the systemi put clover on it own little 8 GB SSD which i can remove and edit on my laptop if i run to boot problems.
So in this example clover is installed on Drive 1's EFI Partition
But OSX is running on Drive 3 so there is no data at all of the EFI partition of the OSX drive
It seems that if multibeast can not find a EFI and/or Clover folder on the system OSX drives EFI partition then it fails, i fix it by manually creating a /EFI folder in root of the EFI partition of teh OSX drive and then create the sub folder /EFI/CLOVER ..
In many cases i think multibeast just checks to make sure that the folder structure exists, but in some cases (like audio) it will try to modify the config.plist so in this instance you would need to copy your config.ini file into the dummy folder structure.
This could be fixed if multibeast could have an option to manually specify the EFI partition in non standard installs ... maybe something for tony and the multibeast team to think about.
Hope this helps
Cheers
Jay
