For the issue with the cluster, ensure you configured the virtual disk controller mode properly (depending on your MSCS setup)
Yes this seems to be one of my problems. I haven't thought about this at the beginning and of course already done some configuration.
Now i cannot change the scsi bus when powering the vm.
I read a workaround by adding a second hdd but i'm not able to add this hdd with a new scsi controller (only scsi(0:1,2,3..) not scsi(1:0))