debugging in mt4

 
have a demo account in mt4.

I have written my first expert advisor script.

I am able to debug it on a live chart, so working fine. I would like to debug it though on historical data. In the MetaEditor the Debug>Start on history data is grey out though.

Also when running the strategy tester my break points never get hit, I put the break point on the first line in the OnTick function so it should get hit in my understanding.

Is this because I have a demo account? If not how can I debug my script on historical data?

 
In future please post in the correct section
I will move your topic to the MQL4 and Metatrader 4 section.