If the switch doesn't cause a single reaction of the top, it will be an electrical problem (not an hydraulic one). So you are definitely looking in the right direction...
Is it possible to manual control the hard- and soft-top? I managed to close and open the front locks, but that was about all.
The roll bar should respond to the roll bar switch as well as to the top-switch.
Have you checked the connectors at the switches (for power and ground)? Do you have dash illumination in the switches (top and roll bar)?
just some thoughts...greetingz,
with a minor 600+k