For your subreport question:
I usually create subreports directly inside the main reports instead of as a separate file. Here's something that may work for you, though...
1. Import the subreport into your main report.
2. Link the subreport to the date params in your main report.
3. Edit the subreport and delete your original date params.
4. In the subreport, modify the Select Expert to use the parameters from the main report (they'll start with "PM" in the subreport) as if they were the original parameters that you just deleted.
-Dell