the leaf tip burn looks like over feeding to me. also royal kush takes upto 14 days plus to show signs of flowering they dont like high humidity witch i think was your problem in the earlier pictures with the deformed groth an drooping im not new to growing but im allways learning ive got 2 royal kush flowerng now at 35 days tomorrow!! 1 in soil the other in a bubbler system. both are fine but seem to be taking ages to really swell out.. im using vita link a,b and bloombastic,canna boost exelerator..