I don't think you can install direct to RAID. I tried doing it by installing to a single disk, setting up the mds, copying the filesystem across, and editing fstab and lilo configuration. It boots up fine, but linuxmce also picks up the md device as a potential storage device, and wants to add it to the list of storage devices (in its irritating way of asking persistently, not taking no for an answer). If you make the mistake of saying yes, you will get all the silly little system sounds and images listed amongst your media. It will work if you are careful, but it could be friendlier.
If I install LinuxMCE to a separate disk ant then if I setup raid and lvm on other disks and copy the /boot folder to non-lvm separate partition and other to lvm this should work? Of course I would also need to reinstall grub.