It appears that the redbukva syntax ~ is only allowed for the Church Slavonic letter range defined by the regular expression. This limits usage of the syntax and disallows for one particular use case: reddening a Slavonic Asterisk with ~꙳. This is not going to be such a problem as long as issue #16 is resolved, but one thing worth considering is that a ~꙳ syntax is simply lighter than =꙳=.

May I suggest one of the following:

1. Add Slavonic Asterisk to the regular expression for the redbukva syntax
2. Relax or remove altogether restrictions on the redbukva syntax

Currently, both XML and LaTeX renderers produce invalid output, because leading part and trailing part are missing.

For XML leading should be something like:

<document>

and trailer should be

</document>

For LaTeX we need leading part of:

\documentclass{article}
\usepackage{churchslavonic}

\begin{document}

and trailer:

\end{document}

Slavonic Asterisk symbol enveloped into kinvar syntax = would not render as expected when preceded by an alphanumeric character.

For example, the following will render the same way as it appears in the editor: Слово=꙳= Слово1=꙳=

If a punctuation symbol or whitespace is inserted just before the kinovar syntax, the abstract above renders as expected: Слово=꙳= Слово!=꙳=

This behavior is somehow specific to the pattern of =꙳= (equals sign, slavonic asterisk, equals sign) only. I didn't manage to discover any other symbol combination that reproduces the bug, including Church Slavonic superscrypt symbols (i.e. =҃=)