There's no need for an additional download to have UTAU in English. Make sure you have a clean installation of UTAU, then go to ツール(T) > オプション(O) > 全般 (first tab) > その他 (second sub-tab) > インタフェース言語を強制する (final checkbox) > Select "en" in the dropdown menu and restart UTAU.
There's no need for an additional download to have UTAU in English. Make sure you have a clean installation of UTAU, then go to ツール(T) > オプション(O) > 全般 (first tab) > その他 (second sub-tab) > インタフェース言語を強制する (final checkbox) > Select "en" in the dropdown menu and restart UTAU.