Update cell based on several IF criteria

I'm trying to automate a column for the users where a "Type" is updated based on the criterion below... This would really save them a lot of time as they deal with over 200 rows per file and they update the type per each manually - this is daily as its changes frequently... please refer to the attachment

Criteria:
IF columns E or F have a total greater than $0, enter MDE in the corresponding row in column D
IF column D already has MDE in the cell because columns E or F calculated 1st to update it, and any column from G - N has a total less than or greater than $0, leave as MDE
IF column D has no MDE because columns E or F equals to $0, than update as CR if row 4 has a CR number
IF column D has no MDE because columns E or F equals to $0, than update as Other if row 4 has an Other
If any of the columns have $0 and row 4 is empty (in this case J - N, do nothing


Note: columns E or F need to be precede the calculation (be calculated 1st) for column D before the other 4...