Pathfinder 2e Critical Damage

Can we get the critical damage based off the original damage roll? I've had situations where players get upset if their non crtitical damage roll is less than their critical damage roll - which I understand. A better approach is not to roll damage twice, once for normal and once for crit, but to base the crit off the original roll. 

I havent seen the sheet, but until relatively recently it wasnt possible to do this - you had to roll them separately.  That was a limitation of the Roll20 platform. It is possible to do it now, but it's not straightforward. I'd suggest messaging the sheet authors directly, and hoping :) They might not notice a random roll20 thread. There might be a dedicated thread for the sheet, and it would be a decent idea to raise it there since those are maintained by the sheet creators.