>Here's some theroetical questions just to further my understanding of how things work.
>
>1. When the application has multiple forms open and each form has a PRIVATE datasession, which datasession is in play when an external PRG is run? I would assume it would be the datasession associated with the form that was active when the PRG was called. Is that correct?

Yes, in runs in form's DS.

>2. What if the PRG is called from a menu selection in the main menu (_screen menu)?

I had a problem when I was using form's manager. The program was using default DS of the manager class, which created it. It may very well be a case here.

>3. Can a form have multiple datasessions?

Unless you create some session based object in the form it should not.

>4. Can a datasession be changed or a different datasession be selected in PRG code?
>
Yes. You can create a session based object or use SET DATASESSION command.

>5. Is a datasession essentially the same as the dataenvironment? If not how do they differ?
>
I would say, they are essentially the same.