Update
With KOMA-Script version 3.19a or newer you simple have to redefine \sectionlinesformat to get the desired result:
\documentclass{scrartcl}[2015/10/03]
\renewcommand\sectionlinesformat[4]{%
\makebox[0pt][r]{#3}#4%
}
\usepackage[headwidth=textwithmarginpar]{scrlayer-scrpage}
\clearpairofpagestyles
\ohead{\pagemark}
\usepackage{blindtext}
\begin{document}
\Blinddocument
\end{document}
Original answer
Since KOMA-Script version 3.17 (current version on CTAN) you have to redefine the commands \sectionformat, \subsectionformat etc. instead \othersectionlevelsformat.
\documentclass{scrartcl}[2015/04/23]
\renewcommand\sectionformat{\makebox[0pt][r]{\thesection\autodot\enskip}}
\renewcommand\subsectionformat{\makebox[0pt][r]{\thesubsection\autodot\enskip}}
\renewcommand\subsubsectionformat{\makebox[0pt][r]{\thesubsubsection\autodot\enskip}}
\usepackage[headwidth=textwithmarginpar]{scrlayer-scrpage}
\clearpairofpagestyles
\ohead{\pagemark}
\usepackage{blindtext}
\begin{document}
\Blinddocument
\end{document}
Page numbering of the front matter in lower case roman
Use the following setup
\definestructureconversionset [frontpart:pagenumber] [] [romannumerals]
If you want additional settings to be applied in the front or bodypart, you can use the command \startsectionblockenvironment. Just for demonstration, this is how you reset the page number to one in the bodymatter:
\startsectionblockenvironment [bodypart]
\setcounter [userpage] [1]
\stopsectionblockenvironment
Don't forget to mark up you content, so ConTeXt knows where the front and bodymatter is:
\startfrontmatter
\stopfrontmatter
\startbodymatter
\stopbodymatter
The rest in Arabic numbers
That is already the default, there's no need to change that.
Title page
A title page is created as follows
\startstandardmakeup
Content of the title page
\stopstandardmakeup
By default the page is not counted. To change this use the setting pagestart=start, here together with other settings to enlarge the font and to centre the content:
\setupmakeup
[standard]
[pagestate=start,
style=bigbodyfont,
align=middle]
Putting it all together leads to the following skeleton:
\definestructureconversionset [frontpart:pagenumber] [] [romannumerals]
\setupmakeup
[standard]
[pagestate=start,
style=bigbodyfont,
align=middle]
\starttext
\startstandardmakeup
Title page
\stopstandardmakeup
\startfrontmatter
\completecontent
\stopfrontmatter
\startbodymatter
\startchapter [title=First chapter]
\stopchapter
\startchapter [title=Second chapter]
\stopchapter
\stopbodymatter
\stoptext
Best Answer
You can use Enrico’s answer in the other question, provided you define a macro that outputs the Bengali numerals, as in the code below:
With this code I get the following result:
Note in particular the Bengali digit 1 as the page number.
I’ll make the Bengali digit code in a package as part of Polyglossia.