Adjustable CC/CV supply with voltage and current limiting having no output voltage at low voltage levels?
Issues I see with this design:

MAX4172 input voltage range issue. The supply of your MAX4172 is + 5 V while the sense inputs are at +12 V. That is not going to work, you will have to supply the MAX4172 with at least 12 V also.

The circuit around Q1 and Q2 will probably work fine. However I would use a simpler circuit, I'd use one NMOS to make M2 switch on. Then the polarity of the output of the MAX9028 will be incorrect, to solve this, swap the inputs of the MAX9082 so that its output becomes low when there's an overcurrent.