I've also had this experience with the Fedora partition configurator. FWIW, you can somewhat get around it by manually creating the partition layout you want (LUKS+LVM+RAID etc), then mounting it as you'd want to use it, then just selecting it from within the partition manager.
This is also the only way I've found to do it with Ubuntu's installer, but once it's set up it works fine.
This is also the only way I've found to do it with Ubuntu's installer, but once it's set up it works fine.