Perform FInd/Replace is used to search for data within a field and changed it, not the step you want here.
Use this script:
Go To Related Record [Show only related records; From table: ProjectedCosts_List; Using layout: "ProjectedCosts_List" (ProjectedCosts_List)]
If [ not Get ( LastError ) //there are related records to go to]
Enter Find Mode  //clear the pause check box
Set Field [ProjectedCosts_List::Date_Start ; ProjectedCosts_List::g_StartDate2g_FinishDate2 & "..." & ProjectedCosts_List::g_FinishDate2]
Set Error Capture [on]
Constrain Found Set
Note: GTRR, does not change layouts if there are no related records, so you always need to check either for the presence of related reocrds for for an error code when you use this step if you have any script steps located after it in your script or they can do some really unfortunate things to your database because they are operating on the wrong layout and/or window.
Note, if ProjectedCosts_List and ProjectedCosts are occurrences of the same data source table, the GTRR can specify a layout based on ProjectedCosts instead of ProjectedCosts_List, but the "from table" parameter must still refer to ProjectedCosts_List, not ProjectedCosts.
OK thanks for the quick reply.
I put your script in and it did filter some results. Unfortunately it is picking up interesting data. Can't work this one out.
The screen layout shows all correct data for whatever start or finish dates you pick. When you select the popup report it shows the correct data for the month of January 2011 no matter what date you select. December 2010 is the first month of entered data if that affects anything. So any help would be good.
Script details -
worked a treat