I recall the ░▒░▒ characters only from the old MSDOS character set, and they have been removed from the ANSI character set in favour of more european diacritics. fortunately the block graphic elements have been saved in the unicode set, so you should be able to use them when you switch all relevant nodes to Unicode.
do you mean changing the character encoding to UTF8?
because ive tried that and ANSI and both just gave me either alt codes or garbage in return in the renderer. i also tried changing fonts to arial, terminal, system and fixedsys.