Mplab stimulus simulator and in general the IDE has nothing to do with your program in Basic. You will never see what is happening in your program once it is compiled (virtually re-writen by the compiler in assembly).

You see the variables only if they are from an assembly program or if Melabs ever permit this to happen through special plug in for Mplab.

Till then, the only thing you can monitgor are the internal registers of the PIC that Mplab can directly show you. For example, if you want to increment Data RAM location $10 for every button press, then you can see the register $10 but not if you name it like My_Variable as it is not easy to find which register this maps to. Maybe others can help you to dig deep into the produced from compiler files to find the infos you seek...

Ioannis