If a table contains text in a cell which is highlighted in colour, when a piece of text is selected subsequentally to add (via the WYSIWYG editor) a link (HTML reference) upon saving the published page is corrupted.

I believe the editor/publishing process get confused with the '|' delimiters across the table and the link and resolved them differently than presented in the editor. This is turn leads to the link be presented on the page directly (rather than as a reference with on the original text). The reference appears either in a different cell and often the row becomes one cell shorter than the rest of the table.