Might be easier if you recreate this in another qvw and upload it, or just post the one you're working on. As you have explained it, it's tough to tell exactly what you're going for. There may be a better way to achieve your solution than you have considered.
if i understand you correctly, i use a similar function in our main application.
We did not link the calendar dimension table to facts table. We use two variables holding the selected min and max date from the calendar listbox (only 1 calendar is used, and with min and max user selections of more than 2 values are compensated)