Am I correct in thinking that that pedal sends just the System Real-Time Start and Stop MIDI commands, but no MIDI Clock? If so, this isn’t likely to work for you:
In MIDI, the Stop command stops the sequencer immediately, but Start just gets the sequencer ready to play. It doesn’t start playing until the next Clock command - and at the tempo of the received clocks. But there are no clocks here, so, at least according to the spec, the sequencer should never start.
That the DT starts at all is probably due to some timeout somewhere inside: Not having received a Clock message in over 30 seconds puts the tempo slower the 0.08 BPM!
That this pedal works with any other devices is a bit surprising… because for it to work the device must be slave sync’d to the pedal (for Start and Stop commands to have effect), but not slave sync’d to the pedal for tempo (since it doesn’t send Clock commands). I don’t know of any devices that support such a mixed slave sync mode.
In any event, do please upgrade to the latest firmware. Many issues have been fixed since 1.04.