Yep, pretty much screwed, 1 HD straight install NO degraded array, two drives on install will get you a raid 1, more as per the wiki, and will also allow access to raid management from console, add larger, remove dud, add new etc etc.
The beta 1 produced a Raid1 with 2xHDs straight up, some new updates now available not related to those functions.
If you are keen to learn something new it can be done, might take some big ones
FS type will also play a part there. We have now found you can choose other fs like ext3/4 lvm and no lvm using the graphic manual partioning in the graphic installer,
***** Warning, until a new beta this will result in a non-booting system that requires a command line change from the start screen by pressing 'e' when the kernel selection screen is shown. There is a bug covering this, once booted there is a package update for grub that resolves this in subsequent reboots.
useful in VM scenarios as it removes some overhead with a slight performance gain and improves access to other features of the hypervisor, access to single file restore from the hypervisor backup functions so I am told.