simple Program Change „drawing“ impossible...

…for me it is just IMPOSSIBLE to simply „draw“ one or two prg changes for triggering a Midi Plugin (StepPolyArp), changing the patterns. I tried with my fingers and with the pencil. It is a mess, its frustrating that i not can just enter a number, instead i have to fiddle around with „drawing“ and deleting unwanted values.
Did i miss someting? I just can‘t believe that there is no chance to enter just the number… Please help.