Calculate time outside of specified ranges

I am staring at this excel spreadsheet blankly ... I am at a loss as to how to accomplish the detailed analasys but simple math this spreadsheet reequires.

The data consists of three columns pasted from a report that is exported as a .csv:

B
Code
C
Start Time
D
End Time

The following analyses must be made on each row:
1. determine if the start time falls within the scheduled shift

=IF(AND(F11>=$B$5,F11<=$B$6),"yes","no")

2. determine if the end time falls within the scheduled shift

=IF(AND(H11>=$B$5,H11<=$B$6),"yes","no")

3. establish how much of each time segment falls within an approved time frame (i.e.: scheduled breaks, lunches, and other approved time frames)

**Step 3 is where I'm stumped because there are so many evaluations that are required. For instance. If the overlaps a scheduled break or lunch then that time is exempted and all I need is the duration outside of the exempted time, and I was planning on making a check box or drop down to manually remove other times**

The spreadsheet has been attached for reference ...

I think I'm way out of my depth and would appreciate any help anyone could give me.

Thanks so much.