Working with Old Babylonian cuneiform in TeXstudio

Here's an example; you shouldn't make Santakku as the main font, because it lacks support for several used characters and it seems much like a poor clone of Times for the non cuneiform part. If your editor has font support, you can even type in the characters.

\documentclass{article}

\usepackage{fontspec}

\newfontface{\cuneiform}[Scale=MatchUppercase]{Santakku}
\DeclareTextFontCommand{\textcuneiform}{\cuneiform}

\newcommand{\AN}{\symbol{"1202D}}
\newcommand{\KA}{\symbol{"12157}}

\begin{document}

This is cuneiform \textcuneiform{\AN\KA}.

This is cuneiform \textcuneiform{}.

\end{document}

You might define a table of equivalents in a file, called cuneiform.tex containing

\newcommand{\AN}{\symbol{"1202D}}
\newcommand{\KA}{\symbol{"12157}}

and the other necessary macros. Put it into a place where TeX will look (this depends on your system, see Where do I place my own .sty or .cls files, to make them available to all my .tex files?) and do

\input{cuneiform}

when you need it.