I'd like to know if there was a specific reason behind forcing the encoding here, or if anything speaks against just leaving these settings away so that Python can detect and use the encoding of the ...

About UTF-8とShift_JISエンコーディング間のデータ変換を簡単に行うPythonプログラム。

It looks like the exported file is utf-16 (at least that's what gives me legible results when I open it using that encoding), but apparently RegSetValueEx wants a utf-8 encoded string?