Agree to the default installation directory (under c:\Program Files).
Agree, if the installation asks about adding shortcuts to Edit Plus. Check the installation and configure EditPlus:
Open EditPlus icon on the desktop.
Press button [Evaluate] and then button [I Agree].
Open menu Tools->Preferences and select category Fonts. Pick "font size" and "language" to suit your needs. Leave the font family "Courier New", since it is fixed-width font and is best suited for the plain text editing.
Select category "Files" and remove the checkmark in the checkbox "create backup file when saving". In this case EditPlus will not create *.bak files when you edit something.
To save a text file in UTF-8 (it is essential, if you are using non-ASCII characters, e.g. in Latvian or Russian language), select from menu File -> Save As and then pick the Encoding value equal to "UTF-8".