prerequisities:
installed medieval2+kingdoms 1.5(preferably licenced). I have XP on my PC, so how does mod shall behave on others sistems, which I hate, I don't exactly know.
install:
1. install Retrofit_1_0
2. extract retrofit.part01 in retrofit directory, replacing content
3. that's all. but just in case: if you forgotten to create shortcut, create it from kingdoms.exe, in properties add mod directory and " --io.file_first"