hello ,i am newbie ,i have several questions ,and can not find in forum and manual artical ,please help me
1, in stratage editor there is build-in function that we can program in MT4 mode ,is that mean we can compile it and use it on Jforex terminal for trade and backest purpose? i have try to backest it but no any result .
2, there is MT4 to Jforex code convertor , but after convert ,the code is not complete ,it will miss many information ,especially trade condition
3,how to backtest a stratage , is it neccessary to add test code in stratage before backtest ?
4,is there any code sample or artical about multiple instrument stratage ?
thanks .

It is only meant for strategy conversion not actual coding. The converter is still under development, meaning that many features are not supported. You have to check yourself if your strategy works properly after conversion.
What do you mean by "test code"? You use the same startegy source code both when running the startegy real-time i.e. with live-data or back-testing i.e. with historical data.
Strategies by default get fed the data of all subscribed instruments, thus strategies by default work with multiple instruments. However, in most of the strategy examples startegies "filter" out the data feeds to work with a single instrument. See more on strategies:
https://www.dukascopy.com/wiki/#Strategy_API
Create your first strategy:
https://www.dukascopy.com/wiki/#Use_in_JForex
Try a simple strategy:
https://www.dukascopy.com/wiki/#Simple_Strategy
See strategies in code base:
viewforum.php?f=7
For more convenient strategy coding, consider using JForex Standalone API:
https://www.dukascopy.com/wiki/#Use_in_Eclipse