I resolved the issue by modifying that file to:
/*
MOD TO DROP QUERY STRING FOR SEO URL
*/
if (!defined("DROP_QS") || (DROP_QS !== true)) { // <= modified
if (isset($_SERVER['QUERY_STRING']) && ($_SERVER['QUERY_STRING'] != '')) {
if (strpos($thePostURL,"?") !== false) {
$thePostURL.= "&" . ($_SERVER['QUERY_STRING']);
} else {
$thePostURL.= "?" . ($_SERVER['QUERY_STRING']);
}
}
} // <= modified
/*
END MOD
*/
but I had to modify the source file as well. Any time that I edit the validations behavior, my changes are overwritten, so I had to modify the source file as well. If these source files all go to xml, that could become harder.
To make the extension more compatible with options like mod rewrite and flexible in general, there should be a flag to preserve or drop the query. It would be great if WA preferences would allow a choice of whether or not to refresh the files if they already exist in the webassist directory (except when updating from a prior version), and a manual refresh webassist files option so that there is more control over such mods.
Thanks
Steven