Excel Conditional Formatting

I suggest using a formula criteria to determine which cells to format.

For the first one, let's assume that cell D2 is the first cell that needs conditional formatting. You might use formulas like:
=D2<0.85    for the red format
=AND(D2>=0.85, D2<0.92)     for the yellow format
After entering the formula, click the Format button, go to the Fill tab and choose your color. Click OK twice.

For the second one, you might use a criteria like:
=AND(COUNT(B2:C2)=2, (C2-B2)>=TIME(0,5,0))     for the red format

Thank you - what if I wanted to check column D and E which are also time values, but I want to check if column E is 5 or more mins less than column D then format red

For the percentage check you can use one of the standard conditional formatting setups and don't need to use the formula based check.

See screenshots below:

Also, are you aware of the Conditional Formatting where you can add icons to the cell rather than filling the cell with a colour.