Ive been working with navigation links recently - specifically Smartlinks, and I found the documentation was missing some important steps, and the example project provided had the same issues.
The problem: AI sometimes ignores OnSmartLinkReached when travelling through the nav link.
The solution:
1 Try using a direction other than ‘both ways’, it seems only 1 way smartlinks are stable.
2 After pressing CopyEndPointsFromSimpleLink, delete the array entries for Simple Link PointLinks (Otherwise it detects the simple links as well as the smart links, and if the AI chooses to travel through the simple link, OnSmartLinkReached doesnt fire.)
Ive submitted a ticket for the documentation update (or rather, Isaac Donkoh-Halm did for me, thanks!) But I wanted to post here in case someone else finds this info useful.
Cheers 