The switch in the KIWI is built into the regulator chip.
There are 2 ways to connect switches.
1) The switch in the KIWI is on when the contacts are OPEN and off when the contacts are CLOSED. If you connect a switch to the switch port of the KIWI you CANNOT charge through it. The switch port is only a logic port and doesn't pass any current.
2) You can add a switch in series between the battery and the KIWI. In this case you essentially have 2 switches in a row (KIWI plus switch) and add extra weight and failure points. I wouldn't do this.
Mine is set up with the pin switch plugged into the KIWI. My RX battery is an A123 with a balance tap. I charge through the balance tap directly using a Cell-Pro charger... don't have to disconnect anything.
Hope this helps.
Also... FWIW... I have my cyclic servos plugged directly into the KIWI, 3 jumpers to the RX, and the everything else runs off the RX at 5.2V. Pretty slick.