You have done an excellent job of assessing the problem and providing the information required for further diagnostics.   Unfortunately, I do not know how to set a Tag ID in JDOffice.   I assumed that they were automatically set.   Within the Deere FODD, we have to create the Tag ID's dynamically, and yes, we create them within that range that was defined for the Client ID.   I have to wonder if the mechanism that is used to create the TagID in JDOffice might not be time-sensitive, and has now gone over range, or something.    I don't even have a box available that JDO can run on.   

Yes, you can create cards for a GS1 with other brands of software.    And, yes, you can add farm and field names, etc, dircectly within the monitor.  However, that won't let you address doing "a few prescriptions".   I suspect other people more familiar with JDO will post with a resolution to your JDO problem, and you can just got from there.  But if you haven't tried to make a prescription in JDO, you might want to cross that bridge before you spend a lot of time making the JDO export work.

Are you trying to generate a single client or multi-client card?