Need an Expert advisor to place a daily trade

Hello,

My basic strategy is to place one trade per day with a set take profit and stop loss.  Whether to buy or sell will depend on price of the traded currency pair compared to the moving average over the last 8 hours of a different currency pair. This strategy has been tested using SAS and I am ready to trade it on a live account so I need to be sure it will work with any broker and on any type of account (it will probably be a spreadbetter account).  

Above, is the main strategy, but I have a couple of extra features that I want to add, so I can try and improve my strategy.

- I would like to have the possibility of a trailing stop, or to have half of my trade as a trailing stop (i.e have two trades one with a fixed stop and the other with a trailing stop).  

- I also want to have the option to move the stop loss to breakeven point after a certain amount of pips.  

- I would like the size of thetrade to be automatically calculated based on % of equity in my account. 

I need to have access to the source code, in case I change how I choose the direction of my trade. I need to be able to edit the code myself asI improve my strategy.

Shona