Adding more defines to existing Laguage NS

I want to add my own defines to some of the Langauge .NSH files for the modern UI. I've tried just adding a line like:

!define MUI_TEXT_URL_TITLE "Enter URL"

into the English.nsh and then in my code using:

!insertmacro MUI_HEADER_TEXT "$(MUI_TEXT_URL_TITLE)" "$(TEXT_IO_SUBTITLE)"

but it keeps giving me a warning:

LangString "MUI_TEXT_URL_TITLE" is not set in language table of language 1033

Is this possible? If not I saw in some other posts where it sounded like I might be able to create another .NSH file that I include and can pull defines from?

I might have found the answer here . Sorry, to bother you.

If you create the installer yourself and just need a few language strings, there is no need to create a whole language file system.

Use the LangString instruction to define a language string.

LangString is what I've been using. I was just hoping to put all my language strings into 1 or 2 files. I'm going to be writing an app to output the scripts to be compiled. So, it would just be easier if I didn't have to keep writing the LangStrings to each script.