change expert mt4 to mt3

 
Hi,
I have an expert on mt4 and I would like to change it for the mt3.What do I have to change in the expert 4 ?Do I have to make big changes or it is simple to do ?

Thank you
 
MT4 and MT3 EA are 2 completely different types of language, MT is C++ type, while MT3 is more like Easy Language type.

So, unfortunately, there is a lot to chanage.

There are one thing I don't quite understand. Some brokers start to use MT4 as their trading platform, however, as far as I concern, MT4 is still a testing version. Isn't it a little risky to do that?

I must admit that MT4 has made a revolutionary improvement on its programmablity by introducing C++ type of syntax. All the other platforms, which have programme functionality, are still based on Easy Language type of syntax.
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