I exposed the methods: getNeighboringCells(), getNeighboringPortals(), getCellPortals(), getPortalCells() and few others, hope they will be helpful
I updated the code: http://www.geocities.com/wael_el_oraiby/basic_app_2.zip
I m still thinking of the best way to do it, I need to get more experience with scene manager before I can say that what I suggest is right. What you are saying however makes alot of sense if the master scene manager is responsable for creating children.That seems like a pretty good solution to me at first. But, if you do that, you should probably go a step further and prohibit the user from directly using the children scene managers' createChildSceneNode methods in order to keep the coordinate system consistent.
This might be a good idea even if you allow children scene managers to handle some dynamic objects because, as I said, it would keep the coordinate system consistent. The master scene manager would then be responsible for creating and deleting scene nodes in the children scene managers.
Code requires cleaning now I think, and more debugging and refining of the Bsp tree code...