Minimum value referenced from another sheet with restricted values? Circular Reference?

Hello,
I've been trying (to no avail) to do the following:
1)Set a cell (B4) in my subsheet to reference a value (K2) in my main sheet (Priority) and check to ensure that the cell (B4) is not less than that value (K2)
2) If the cell (B4) is less than that value (K2), I need it (B4) to set itself equal to that value (K2) which is a minimum value calculated by formulas I did on my main sheet (Priority)
3) I had originally limited my my cell (B4) to whole numbers between 1 & 10 using data validation (the dropdown makes it easier to use for my purposes), but I kept getting circular references while doing trying to do the above. I've tried with both cells having the same validation, but no luck. The circular reference went away after I eliminated validation on both cells, but I'd really like my drop-down back if possible.

I'm new to writing excel formulas as this project is more of a hobby than anything else, so any pointers would be appreciated.
Thanks

A few things I've tried so far in B4 formula box:
=IF(B4<Priority!K2,Priority!K2) {Get a circular reference}
=IF(Priority!K2>=B4,Priority!K2) {Get a circular reference}
=IF(AND(Priority!K2=1-10,Priority!K2>B4),Priority!K2) {Returns B4 still as 0, K2 is 1 currently}
...and a bunch more I discarded before now.