Taxonomy Plugin – Linked taxonomies

So anybody here that got linked taxonomies working 100% with the custom taxonomies plugin like in Mark’s video? My problem is: I create taxonomy A (“main Taxonomy”) and Taxonomy B (“sub taxonomy”) and link them just like in the video but on my side when adding a listing only some sub taxonomies are loaded after selecting a main taxonomy even though they are populated in the backend. Anyone else had this problem? And perhaps found a way to fix it?