Modifying an existing excel time formula

Hi All

Looking for some additional help to complete my workbook. I have attached a sample data sheet with the rows high lighted in green. This is what the current formula is doing and the rows high lighted in yellow is the results I will like to see. Pretty much everything on the sheet is working well except for the high lighted issues.

More than likely the formulas in M and N will need to be modified to accomplish what I need. If you need to modify anything else or added any new formulas to achieve the end results that I am looking for please feel free to do so.

Thanks in advance for any help and / or assistance you can provide.