Drobo has become read only and can't be changed My Drobo that acts as my media server and Time Machine host for my family's Macs has become read only. While this would normally be a nuisance, it's become a real problem in that I can't change it back from the Get Info Window I've also tried chmod +w to no avail. Any hints on what to do?

In the attached photo, you'll see that the options are dimmed and say that I should have access, but the disk is still read only.

Get Info Window
I would suggest following the official support guide for this issue available here: 

http://support.drobo.com/app/answers/detail/a_id/42/~/why-is-my-drobo-storage-device,-connected-to-my-mac,-suddenly-read-only-and