SQL Connectors with Multi period selection dynamically

It's not possible (for good reason) to have drop-down / combo box selections on the Import step on an Import workflow.
For the date range selection on the SQL, this is usually performed by the end user making a conscious decision to select (a) A particular workflow profile, (b) A particular year, (c) A particular scenario.
The workflow profile settings, and the scenario settings have various attributes such as Input Frequency, sometimes scenarios contain start/end periods (scenarios with custom range), workflow profile properties determine the tracking frequency (e.g. monthly for actuals, 12 periods for budget )

If you have drop-down boxes on the import step, for ad-hoc user period range selection, then this would be very error-prone.  You could do this by building a simple dashboard, and then have an import workflow profile of type : [Workspace, Import, Validate, Load].  The first step (workspace) runs a simple dashboard with your drop-down period selections , and that runs a query to pull data into a sort of pre-staging table, then when you go to the Import step, it pulls the data retrieved from the dashboard into the main stage tables , where the transformation rules can work from.