Somehow, you have the brake light switch tied into the control circuitry for the jacks. On my Southwind there are only 3 prerequisites; engine must be running, parking brake set, and tranny in park to make the jacks work. Was part of the security system you removed connected to the brake light switch? You might be better off talking to Fleetwood about it.
2004 Southwind 32VS
2014 C-Max toad