After 2.5 hours on the phone with Linksys Tech Support (or lack thereof), I finally have a solution to the problem; Return the NAS for a refund.

It turns out that Linksys NAS products will not support multi user databases. You can view data but you can not edit data while more than one user has the given table (file) open. Linksys says this is normal behavior for file servers and the way MS Office and other similar packages expect the file server to handle the files.

Hopefully this will save someone from several hours of hair pulling frustration.