to increase rank in kama u need fast killing and killing the "big" mobs also...u need to be the lower lvl of rim kama - example for kama 75-80 a lvl 75 player will always do better score than a lvl 80
use as much skills as you can , kill as soon as mobs spown , overhit as much as possible, dont let mobs use skills, you got more point by killing higher level mobs (void = best) there were table that writes point count for each your move somewhere in l2ru forums.
i go to rim kamaloka and get the same reward everytime i dont see any points anywhere only know that rim kamaloka lasts for 20 min then the dude shows up and he gives u the reward and thats it
you get different rang (depends on how good you killed mobs) from d grade to s grade (g grade in 80-85lvl kama). the higher grade = the higher supply box you get. the higher supply box = more elixirs, ssx and bssx, eax. from 80-85 supply box you can get attribute stones and ews/bews randomly. also you get essences which can be exchanged for some items.
closing old/inactive thread, questions answered please refer to the following link for rim kamaloka information and rewards - http://l2wiki.com/rim_kamaloka moving thread to archives.