Excel 2010 :: Accessing VBA Module From UserForm On Workbook Open

I am using Excel 2010 and late binding to generate reports. The sheets are blank and unused. I have the UserForm being opened on Workbook_Open and the actual VBA for doing the work in a separate macro in the workbook. All the posts I have found are dealing with accessing cells from the UserForm and I haven't found any dealing with connecting a macro to the UserForm output.

My question is this: I want to return from the UserForm the flags of which reports to run to the (unopened) macro containing the code to do so. How do I open the macro and pass the variables to it?

The UserForm is creatively called "SelectionForm" and the macro is called "DailyFTP" with a Main sub as the entry. I know I can use the code under to capture the radio button and checkbox choices. I have other variables like the names of files set as global variables in the DailyFTP macro. The macro doesn't exist until SelectionForm opens it, so they must be set after the macro is in memory.