SUMIFS with vertical criteria and horizontal criteria (horiz. crit. is a date range check)

Hi All,

With reference to the attached cashflow (still in it's embryonic stages at the minute - trying to modify an extremely complicated version I put together a few months ago in a way that makes it much more ergonomic and user friendly).

Tab 'MASTER' will be where I keep the detail of all expenses, frequency of payment, cost etc.
Tab 'SUMMARY' attempts to condense this information so the reader (Head Office) can have a clearer, more simplistic view over where the cash is being spent (they can always refer to 'MASTER' should they require more detail).

In cell D8 of the 'SUMMARY' tab, I want to create a formula that sums the total cost of expenses using the following rules (I will use column D and row 8 as an example but the rules can be extrapolated to the rows and columns below and to the right respectively)
- cell D8 must sum those expenses on the 'MASTER' spreadsheet who belong to the 'Staff Costs' group
- of those expenses, cell D8 must only sum those which are expected to crystallise in that given week (the given week shows on row 7 of the 'SUMMARY' tab and ends the day before the date on row 7 in the adjacent column. The date that the expenses are expected to crystallise are given on the 'MASTER' spreadsheet in columns X - NY
- as such, cell D8 on the 'SUMMARY' tab should currently show a total of $600 because there are two expenses ($350 and $250 respectively) that are classified as 'Staff Costs' on the 'MASTER' spreadsheet, which are expected to be paid on or after 01 January 2016 but before 08/01/2016.

PS I'm due to catch a flight within 40 minutes so if someone could assist before then, I'll have something to do for the next 7 hours

EDIT: Apologies, had to change the attachment. The previous one contained specifics. It seems I uploaded the wrong one