[caffeine]

I was looking at those ones. As channel 5 is the switch channel, they provide it as a pad on the board (see left most PCB in this image), but you don't need to use it.



You should connect the battery balance red lead to the 'VBat' pin shown in the left and middle images. Don't stick it on pin 7!

Here's a good illustration of where to wire everything:



The only drawback seems to be having to separately update the firmware on 2 different boards.