I think I already replied to you in email, but I wanted to respond here in the forum also in-case anyone else has this issue.
About 99 % of the time this sort of issue is the result of the editor converting the url into a hyperlink which adds html between the [hmyt] tags that the plugin cannot handle. Usually when this happens, the plugin will display the text similar to "The text to be replaced." To fix this just click the editor's unlink button while the cursor is on the url.
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