Good Morning
I did encounter the same problems with amarra mini and the Drobo FS.
Contacted Sonic Sudio and they were of great help, mail Dietrick Hardwick,
and he can sent you à link that cures all problems.
I was sent the following link for the mini cure
www.sonicstudio.com/releases/Amarra MINI 211 Release 4265.zip
Good luck
Robert jc Kleuskens