I've attached this zip file for you guys. (If you cannot download or unzip: here is the mirror: Index of /cowabunga)
This zip file contains 2 files: Cowabunga (lastest version) + fixed version of MACD (i.e. if you have original MT4, and you run MACD, it looks different to MACD on OandA platform, reason is... read back page 4 or 5)
Unzip those 2 files to folder MT4\experts\indicators
note: MT4\experts\indicators not MT4\experts\ nor MT4\experts\scripts
where MT4 is the directory where you install your MT4 (example: C:\Program Files\MT4)
How to run?
Open a blank 15m chart with nothing on it (except the candle sticks). Then insert indicators -> custom indicators -> Cowabunga (lastest version) not Expert Advisor or something else.
Then zoom out a little bit on 15m chart, you should see some arrows on top or bottom of candle sticks.
If the arrow is on the top of a candle stick, it always heads up, this means we should go long (buy)
If the arrow is below a candle stick, it always heads down, this means we should go short (sell)