Parameter difference Ardupilot and ArduRover

Hi
I am a new user with Cube Orange+ and ArduRover, Omni3, for boats.
Is there a way to find the differences between the systems, in that I spent quite a while looking in the parameter listings and help files, for parameters like FLTMODE_CH, and BRD_SafetyEnable, without success. Eventually I guess that these are replaced in v4.4 Rover with MODE_CH and BRD_Safety_DEFLT, respectively? My next step in the setup is ESC settings. (Is rudder available as a servo option?)
Many of the guides, setup instructions, etc., are written for the larger user groups, while Boats would seem to be less popular, so it would be prohibitive to have specific instruction for each arrangement?
In no way is this a criticism, but as a new user, the subject is so large and quite confusing, that it seems likely that others may have worked their way through these setups.
Many thanks.

Best to raise this at Ardupilot forum, https://discuss.ardupilot.org

Hi
Further down the line of exploring the system on the bench, before being built into a boat, following the setup instructions of the Herelink controller, setting the mode in Solex, there appears a situation…
In the buttons page, I can select e.g. Button A short press, then choose Flight Mode, from the drop down, then selecting the gear wheel, there is nothing showing.
As this is a MAVLINK setting to the receiver and CubeOrange, which was on, bound and connected, could the lack of Flight mode drop downs, be due to the MAVLINK looking for parameters in FLTMODE…, while the latest ArduRover v4.4.0 beta 11 has migrated all the FLTMODE_CH and FLTMODEx_ settings to Mode_CH and MODEx_ respectively?
A workaround could be to set the modes by SBUS switches, but would all of the ground controllers recognise this? Of course should there be receiver signal losses, then the mode would be lost, but if the default is to hold position, then for a boat this shouldn’t be too much of an issue, with respect to falling out of the sky. ?