Zigzag has never been available on my knowledge on Transpeak. Zigzag plus is also available on Kinchbus's skylink service but is still not accepted by Stagecoach on Pronto!
Non of the Dove Holes routes are mango equipped, the system requires a new init ticket machine, Dove Holes still uses the older 'almex machines'
Incidentally, init machines are all the same colour, so perhaps if they had changed over, they would have avioded that embaressing incident where the bus wa delayed whilst they replaced a red machine with a green one, to match the livery of the bus!