OK, thank you for the information.
If the control board resembles the board pictured in this link: http://powergearus.com/documents/312.pdf
then, yes, that's the controller. Or, where you replaced the fuse is the 12 volt distribution panel. If there are also 120 volt household style breakers located there, then that's the distribution panel, not the slide out relay controller. Most often, Fleetwood located the relay control in the wall/cabinet behind the slide out switches. However I have also seen them located in a lower cabinet and the outside electrical compartment.
This is a link to the slide out service manual: http://www.powergearus.com/documents/Serv_Man_Electric_Slideout_Sys.pdf
It's a large download, about 3.5mb. Here is a link to troubleshooting the relay control: http://powergearus.com/documents/329.pdf
You're going to see two different part numbers for the relay control. The original was part # XXXXX which is probably the one you'll find. That relay control has been replaced with 14-1130. The relay controls don't require placement of the room in a certain position. That's for rooms equipped with the dual amperage sensing control, which you don't have.
Thinking about it, you might check the outside compartments first, somewhere near the batteries, probably. The room starting to operate on it's own is usually indicative of low voltage, moisture/water on the board, or a faulty controller. The fact that the fuse was warm (I'm leaning towards the fuse was in the distribution panel) and the room moving without any input from the switch makes me suspect water/moisture is present on the control board. The board is equipped with fuses/circuit breakers. If the fuse on the board is blown, then you won't have any pass through of current to the motor when the operating switch is pressed. The current flow is: 12 volt distribution panel to the relay control to the slide room motors. The switch is merely a trigger that sends a pulse to activate the relay. If the fuse on the board is blown, then no current can get to the relay to pass through to the motor.
Worst case is upgrading the relay control to the current version.
If necessary, you can manually crank the other rooms in, or disconnect the motor leads at each room and jump them to a battery to long enough to operate the room directly at the motor. If you decide you need to jump the motors to a battery, the motor leads are not polarity specific. If you connect red to positive and black to negative and the room tries to move out when you're wanting to bring it in, simply swap the motor leads with black to positive and red to negative.
Once you locate the relay control, use your meter or a test light to check both sides of the fuse(s) for power.
I strongly suspect the relay control is the issue.
Let me know what you find.