DPA Switch Compensation Capacitor

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I am designing a DC-DC Converter with DPA Switch.
Input is 36-57 VDC and the output is 5V, 3.5A.
My Questions are as below:
1) I am getting a message "Selected Value of compensation capacitor is smaller than recommended. This may result in smaller phase margin". What action needs to be taken for this?
2) Can I replace 1N4933 and 1N4934 with S1B?
3) Can I replace 80SQ045 with SDT10A45P5 if the Board is Active Cooled using a Fan?

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Hi Agrawalcomputers,
Thank you for your interest in using Power Integrations products.
Regarding your questions
1. Could you share the spreadsheet for your design? It would be suggested to use the recommended capacitor value for stability.
2. Replacing the 1N4933 fast recovery diode with S1B standard recovery diode, the DCM ringing on MOSFET drain to source might be gone, which might affect the efficiency.
Replacing 1N4934 to S1B will result in higher bias voltage, please measure the bias voltage.
3. Yes, you can replace the 80SQ045 with SDT10A45P5, as long as the PCB trace area is large enough to dissipate the heat.