Felix,

your example contains a lot that is not relevant to your question. Try to reduce it.

For number types, use the "conversion" option, for Roman numerals, there are the values r, R, RK, or (lowercase, uppercase, small caps, with bars). See also https://wiki.contextgarden.net/Command/convertnumber

Any "command" options accepts the name of a macro, "numbercommand" needs a macro with one parameter; don't try to call a macro here.

For the dot after the number, I'm not sure, try "sectionstopper={.}".

Hraban

\setuppapersize
   [letter]
   [letter]

\setuplayout[
     backspace=0.5in,
     topspace=0.5in,
     header=0in, % No headers
     footer=0in, % Space for the footer
     width=middle,
     height=middle,
]

\definefontfeature [default] [default] [trep=yes]

\definefontfamily [TimesNewRoman] [rm]        [Times New Roman]
\definetypeface   [TimesNewRoman] [mm] [math] [stixtwo]

\setupbodyfont [TimesNewRoman,12pt]

\mainlanguage[en-us]

\setupindenting[yes,0.5in]

\setupheads[indentnext=yes] % To get indentation after section numbers, use this

\setuphead[part][
  page=no,
  placehead=yes,
  numbercommand=\groupedcommand{}{.} % Add period after numbers
]

\setuphead[chapter][
  page=no,
  numbercommand=\groupedcommand{}{.} % Add period after numbers
]

\setuphead[section, subsection, subsubsection, subsubsubsection, subsubsubsubsection][
  numbercommand=\groupedcommand{}{.} % Add period after numbers
]

\setuphead[part, chapter, section, subsection, subsubsection, subsubsubsection, subsubsubsubsection, subject, subsubject, subsubsubject, subsubsubsubject, subsubsubsubsection][
  before=,
  after=,
  style=sc, % Small caps style
  align=middle, % Center the section titles
  ] % it seems that when I make this into setupheads and delete the first square braket set it will not result in what I want

\startsetups document:start
     \centerline{\documentvariable{title}}
     \centerline{\documentvariable{author}}
     \centerline{\documentvariable{date}}
     \blank[line]
\stopsetups

\startdocument[title=Title,author=Author,date=Date]

\startpart[title=one]

\stoppart

\startalignment[middle]

{\sc 1. one} % there is added space as shwon when trying to emulate what I want through regular text

\stopalignment

\startchapter[title=two]

\stopchapter

\startpart[title=three]

\stoppart

\startchapter[title=four]

\stopchapter

\startsubject[title=five]

\stopsubject

\stopdocument

with this code I'm trying to get it so that part, chapter, and the 5 section levels will have roman numerals. I read the docs but didn't get the result I wanted for roman numerals and can't seem to figure out how to get rid of the tiny space that is after the period in the section stuff. Would love an answer for this.
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