Newb OMV install - Disk Housekeeping

Hello

I have OMV v1.13 installed, kralizec, kernel 3.2.0-4-amd64 intalled. As a survivor of a previously bricked NAS device I moved my surviving disks over to an old AMD PC to install OMV. I'm extremely pleased with OMV but have some disk configuration questions.

I have 3 devices showing up under 'Physical Disks'
dev/sda - 186 GB
dev/sdb - 1.82 TB
dev/sdc - 1.36 TB

When I set up OMV I did not configure the RAID. Of the 3 disks used, dev/sdb and dev/sdc were previously paired/configured on the NAS as RAID and dev/sda was on the old PC where OMV was intalled. Upon boot I was thrilled to access the previous RAID configuration with no loss of data. There are some status warnings though.

Under 'RAID Management' the disks show up as:
Name - blank
Device - /dev/md127
State - clean, degraded
Level - Mirror
Capacity - 1.36 TB
Devices - /dev/sdb2

Name - blank
Device - /dev/md126
State - clean, degraded
Level - Mirror
Capacity - 1.36 TB
Devices - /dev/sdc2

Its a problem that dev/sdb is a 1.82TB disk but only 1.36TB is being used, a .5TB difference.

Given this disk configuration I have two questions:
1. How can I fix the RAID status such that it does not indicate 'degraded'
2. How can I access the .5TB unused disk space on dev/sdb and use this as normal file storage? I realize that I can't RAID the unused .5TB, I just want to use it as file storage.

Any guideance the forums can provide would be greatly appreciated

OK I think I resolved my item 2, accessing the .5TB unused disk space, with a few mouse clicks as:

Started the GNOME GUI by burning the Debian 7 Live image and running it from DVD. From the home screen select
Applications->Accessories->Disk Utilities
Select the troublesome storage device
Select the unused storage and create the volume /filesystem (something along those lines ... I can't recreate the exact steps as the disk has been fixed and I can't undo my changes to write this!)

Any guidance on how to fix the RAID status would be appreciated. The above mentioned disk utility allows me to select the RAID array, but the Live DVD couldn't start it. The state is reported as 'Not running, not enough components to start'.

I'm wondering if I need to install the full Debian 7 over OMV, fix my RAID via the disk utility (hoping it can get it started), then re-install OMV.