There is an Action for Refresh Custom Report Widget which allows for parameters to change the content of the Report.
You can have Text Editor Widgets on the screen for accepting start/end dates (or whatever else you need) and use those values as input/filters for the Report Widget. Then you have something like an Automation Command Button on the screen to trigger a Rule to read the text editors, and refresh the Report.
Both my Payroll Screen and Account Statements screens have such mechanisms.