Thank you for your reply. Hearing about your implementation of user defined fields was reassuring to me; that I was headed down the right path. I hope you won't think of me as an ingrate for not responding earlier. I had a couple pressing irons in the fire.
I'm making progress on a program for maintaining user defined fields in a tab attached to a standard maintenance program. Here's a screen shot:
The program is a utility in the sense that input elements that show up on the screen are based on meta-data defined elseware. The program still needs a lot of work.
One thing that's missing in this utility is the ability to upload and attach files to the entity that's being maintained. I now envision a separate tab and program for adding and deleting attachments.