... since Torsion does not work or not work well on LInux...
These terms should be mutually exclusive, it either works or not, if it works then its quality is variable.
Given that torsion is now MIT, and given that it uses wx as its UI it should operate on a cross platform basis. I know its old and outdated but it functions, and its minimalist feature set already improves over and above just simple syntax highlighting that other editors offer.
If all you need is an editor with highlighting, then probably geany is a good choice, it has project options and highlighting which covers most of torquescript most people ever need *
Also has plugin capability so it is possible to fully adapt to torque