amibroker afl writing project

i m using amibroker 5.40. i want to make one afl. Description of the chart: AFL type: Chart only (want this to be in separate pane not on price pane). So there will be only two line Green line for bulls and red line for bears. The pane should display the values on pane in numeric values. Working Timeframe: 5 mins and 800V (constant volume bar of 800Volume) Base Timeframe of Database: tick data Ami version : 5.40.3 basically what i want i have tick data base. and i have tick data available. Let i m working on 5 min TF. So i want Bear Volume and Bull Volume at each bar of 5 min TF. example: the new bar started at 10.00.01 hrs the lets say that price at first tick of this bar changes from 1000 (this is the value of last tick of previous bar) to 1001 and in this tick volume is 10. so at this moment the bull volume is 10 and then on next tick Price changes from 1001 to 1003 and volume on this tick was 150. I want to sum these two volumes 100+150 = 250 and put it into BULL VOLUME. On next Tick the price change is from 1003 to 999 and volume is for example 100 then add this to BEAR VOLUME as there was no bear volume available at this tick so the total bear volume at this bar becomes 0+100 = 100. On next tick the price changes from 999 to 998 and the volume is 15 so the bear volume becomes 100+15=115. on next tick the price changes from 998 to 1000 and the volume is 35 so the Bull volume becomes 250+35=285. i trade 5min TF and 800V (800 constant volume bars) but it would be great if you can make these values variable.