However I don't know/think it can be set from the mpi file.
I will send my .mpi file to freedesktop.org and I suggest you open a new bug for the max_sector problem. If my suggestion above works, maybe add this information to the new bug and comment here to let us know the new bug number.
Thanks for your test.
For the max_secors issue you could add something like this to the udev rule I guess :
RUN+="/bin/sh -c '/bin/echo 64 > /sys/block/ %k/device/ max_sectors' "
However I don't know/think it can be set from the mpi file.
I will send my .mpi file to freedesktop.org and I suggest you open a new bug for the max_sector problem. If my suggestion above works, maybe add this information to the new bug and comment here to let us know the new bug number.