I was wondering if there is any problem putting a delay in a signal script.  For example, this code would be added to the signal library in the screen load script:

[mc.ISIG_INPUT1] = function (state)
   if (state == 1) then   
      wx.wxMilliSleep(5000)
      mc.mcCntlEStop(inst)
   end
end,

This is just an example for simplicity sake. My question is, will I screw anything up by putting a delay (or a loop) into the signal script. In my mind, this code would receive a signal from input 1 while running some g code, continue running that code for 5 seconds and then trigger an estop. Am I correct in thinking this?
Again, this is just an example to keep my question simple.

You should avoid using wxMilliSleep as you will freeze the whole GUI especially for delays that long. Instead you should use wxTimer or the PMC

Thanks for the heads up SwiftyJ! I'll use the wxTimer instead.