A few more confirmations:
-Only the 42T and the 44T are curved (the curve is to improve the chainline)
-All chainrings are for "usual" chains. They have no versions for different chains (different speeds)
-Breaks and throttle are bypassed in the VLCD5 display to its internal connectors, therefore one common cable connects motor and display
-Since the XH18 has no connections for breaks and throttle, this is achieved with different cables that connect to the motor
I was able to add the throttle with the Y cable (3 ends, motor/display/throttle) , and I am able to add breaks with another (X?) cable.
The throttle and break functionality are already in the controller.
After all the throttle is (in simple words) a kind of hand-torque regulator, and
the breaks are nothing more than a switch off signal as far as I heard.
In fact, the breaks could simply be a switch that opens the circuit and connect in series with the throttle!
You get the right cable according to the display and/or throttle/non-throttle version you buy.
This makes sense, the solutions is more versatile this way, but it might not be 100% correct for old controller versions which where developed with only the VLCD5 in mind.
Finally, this is the coulomb meter I use. Tracks AH (remembers values even if the battery is switched off), displays W V Capacity(AH) and Capacity(time). This last one is very useful, it estimates how long can you keep pedaling at the current assist level. If you do not know your battery capacity, you can set any capacity and after one cycle you can calculate and set the true value.