I've used this device in the past, and it worked well, using just the calculated values from the spreadsheet
(buck topology). I picked a value higher for the inductor, to ensure it would work due to tolerances.
Your inductor value looks low - is that what the spreadsheet calculated for you?
For my particular application at the time, the inductor value was higher (and I was operating at 150kHz).
I don't know if breadboard is good or not - the design was PCB based.