try to change your report settings to 'select distinct records' to eliminate the dupes.
If that works ...
If your calc is using 2 different fields create a formula to combine them.
You can use the insert summary (sigma sign) on the new formual field as a SUM at your group1 level.
Create another formula for your day as you did but make that a MAX at your group 1 level
Then try and suppress using these 2 summaries togther, something like:
MAX(weekdayformula,group1)-SUM(other formula,group1)