dates, in FM, are stored as numbers, behind the scenes. So StartDate>0 AND EndDate>0 should work for you.
So, once again, I did not carefully read your post. When you say the last line doesn't take, does that mean that DateStart is populated, but the DateEnd is not?
Thanks for your response. The (date start) field fills in with the "≥" but the (date end) field remains blank. The user still needs to select the actual dates they want to search from - to and they need to select the client. I'm just trying to set something up that pre-fills parts of some of the fields in search mode. The user would then fill in the rest and run the search.
I see. The issue with the script is that you're populating date fields, I think. If you can use text fields to capture the query, it'd work as you expected.
Make sure that your fields that are being set to a value while in find mode do not have global storage specified.
David's example should work for you and the pause while in find mode will allow the user to enter additional criteria.
However, there is another approach that may be worth considering:
While in browse mode, have the users enter criteria into a set of global fields. Then enter find mode and transfer the criteria from the global fields to the fields where they are needed for the find, inserting any needed operators while doing so.
Here is a thread with a number of such scripted examples: