Take a look at the FAQ:
https://windowlight.co.nz/godzoneWP/faq ... s-at-nzdn/The Dunedin installer calls three third-party installers, one of these is SODE (Sim-Object Display Engine) which controls the jetways. You really need to follow the manual to make sure that you don't miss any of the activation steps. The linked FAQ explains what can go wrong, and how to fix it.
If you have installed SODE, and activated it as shown in the manual, but it still doesn't show the jetways, let me know.
-Robin