Ok, everything makes sense now. Maps comes with "basic" junction views (under About->Content it showed as "Junction View")
If a map maker choose to create their own junction view .fjw/.fjv then that will get shown (under About->Content it showed as "Junction View NG")
You can not use .fjw/.fjv of one map vendor on another, it will showed "grayed out" and not red because file can't be used but license allowed.