There are several things to do if you get the Invisibrake from Roadmaster to make it safer.
1. Don't use the diode setup install. find yourself a actual Toad wiring brake harness
Dinghy Towing Harnesses
This replaces the unsightly hot diodes and places them into a nice small package. Also you may not have to splice into your wiring harness.
2. The 4 wire harness that leads to the front of the Toad needs to be capped and dielectric grease in it when not in use. ( this fixes the issue with the end getting wet and causing the system to come on and apply the brakes) or just add a power on/off switch in the Toad to shut it off when not in use.
3. Change the connector on the front of the Toad to a 6 wire connector so that you can hook up to the 12v charge line coming from the MH. This will be used to charge the Toad's battery.
You will also need to change both ends of the MH to Toad cable, hookup the 12v on the MH side and change to a 6 pin on the Toad side.