Also, is there any benefit from 64bit architecture ? I am just training and testing own scripts, writen directly in Zorro "simple C".

Using C++ as script language has many advantages. Additional development tools, such as the Visual Studio debugger and profiler, are available. External libraries, such as Boost, can be integrated without a wrapper. The 64-bit mode can access more memory for backtests. All lite-C functions and all system variables can still be used, but additionally you have C++ classes and templates at your disposal. Error handling is more strict and you'll get warnings about bad code style. The VC++ compiler is a bit slower than the lite-C on-the-fly compiler, but is only invoked when the script was changed. The resulting code runs equally fast or - in 64 bit mode - even faster. The only disadvantage is that you have to download and install Microsoft Visual Studio™ 2017 or above.