The original one was a native executable and this one is build in .NET by utilizing a Mono.Cecil library to get the assembly information so if I would have to answer your first question I would answer - no, they are not the same.
Not sure about your second question as original one was Windows executable so there's no point installing it on Linux. I would ...
If you have U-Boot shell, changing bootargs environment variable to add the single keyword and then issuing the boot command should drop you into a root shell. Use printenv to see current args and the boot command.
IDA does not update memory map after each step since it can potentially take a long time. You can try to either use “run to”(F4) instead of stepping or force refresh by calling refresh_debugger_memory() IDC function.