First off, a few interesting points about Windows System and User DSN definitions, in this case, connecting to a SQL server using SQL server authentication (ie, not Windows based authentication). The DSN definition lets you enter a username and a password, and gives the impression it's going to store it. It doesn't store it, and it's not meant to. It also lets you change a number of paramaters, which it won't save either. Very strange behaviour, but it's apparently normal. In my case I was referencing the DSN in a Notes Client application using a @DBCommand, so I just stored the actual credentials in the system profile (one login for many users.. eek) and pulled them from there using @GetProfileField.
The next thing about the DSN definitions is more related to SQL security. In this case, the user had been setup incorrectly - they had read access to the table, but they didn't have access to anything else. SQL server now requires that you select/deselect all the operations a user can do to a table (run SELECT statements, delete/insert, etc etc). So it's possible to create a user who technically has read access to data, but they have no way to ever see any of it because they can't issue a select statement - the DSN setup will say "Test Passed!" when you click the test button if this is the case. I guess the lesson here is to go and stand behind the person who setup the user, and hope that your 25 seconds worth of SQL server knowledge will help troubleshoot the problem.
The annoying thing here being that it was perceived as an issue with the Notes application.. *sigh*
Secondly, while perusing the options properties box for a keywords field (as you do), I wandered across this neat little field option:
It might not look like anything overly exciting, but it's pretty handy. The issue with the field level LotusScript OnExit event was always that it was possible to close/exit a document without triggering it, even if you'd just changed the contents of the field. This might not happen a lot, but the fact that it was possible was enough to deter me from using it in the past. Thinking back, pretty much all of those times this little option would have made life a lot easier.
I'm not sure if it's a good thing that I'm still discovering new things in the Designer client after using it for so long.