You are doing great work! Your analysis suggests that the Altura might be working just fine, except for the display! Go ahead and plug a MIDI cable into the device and connect it directly to the MIDI IN of a synth. (Do not try connecting to a computer synth for a first test.) Make sure you plug the sensor cables in correctly, not backwards. You had it correct initially. Point the sensors up toward the ceiling, not down to the table. Set the knobs as described in the Quick Start guide: left, right, 9 o’clock, left, left, noon, noon. This should give you one octave of C Major on the right sensor, and control over modulation or note velocity on the left sensor. The unit will default to transmit on Channel 1 on power up. Go ahead and see if you can control your synth. Do you see any activity on the MIDI light on the slave synth?
When he is able, Altura designer Brach will comment on possible faults in the circuit that could account for the display’s power issue.
Good work! Hey, this is part of the fun!