I have done some conversions of my own and it took as much time as to write the original MT4 code. I know this will get better with more experience, but the biggest concern will be testing and I don't think that will be easy. I won't go into all the techie details of why the conversion can't be automated, but I will say that non coders won't be able to do the conversion. Even for coders, there will be a challenge when working on unfamiliar code to figure out what the code was intended to do.
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