Ok guys... I am getting nowhere with this so I have stripped down everything and left with the basic Chartboost functions.
I keep getting the NETWORK_FAILURE when I request for cache interstitial or reward video.
I am using R292.22 and it compiles into apk nicely.
Also I have given permission
ACCESS FINE LOCATION
ACCESS NETWORK STATE
ACCESS WIFI STATE
WRITE EXTERNAL STORAGE
WRITE MEDIA STORAGE
Can someone try out with their working chartboost IDs and see if it works.
I am not sure if the fault is with Fusion or Chartboost setup.