I spent a few minutes last night trying to get SPICE working in KiCad and ended up on google. It turns out they have some generic devices, but you're meant to download the SPICE...
This is great but why cannot you do it? I think it is cheaper, no mechanics (that can fail), easier to build and only you have to disable it by software. Even if user pushes the button, nothing will...
Yes, that explains everything. Unfortunately, I can't use the HSERIN/HSEROUT ports available in the 18F4550 because they are already taken doing the hardware communication. Increasing the baud rate...
Re: CircuitLab simulation
Have not tried the KiCAD yet (as well) but LTSpice, despite its primitive environment, it is easy use, at least for the basics.
Ioannis Today, 20:00Worth to give it a try.
Ioannis