Got the installer working. Fixed a few bugs including a nasty-to-debug issue where the lang_id was being hardcoded during installation, resulting in strings being inserted with the wrong lang_id causing an infinfinite loop with fetch() throwing a "no strings" error and using template (which calls fetch()) to complain
tinyMCEPopup.requireLangPack();
function init() {
var f = document.forms[0], v;
tinyMCEPopup.resizeToInnerSize();
f.numcols.value = tinyMCEPopup.getWindowArg('numcols', 1);
f.numrows.value = tinyMCEPopup.getWindowArg('numrows', 1);
}
function mergeCells() {
var args = [], f = document.forms[0];
tinyMCEPopup.restoreSelection();
if (!AutoValidator.validate(f)) {
alert(tinyMCEPopup.getLang('invalid_data'));
return false;
}
args["numcols"] = f.numcols.value;
args["numrows"] = f.numrows.value;
tinyMCEPopup.execCommand("mceTableMergeCells", false, args);
tinyMCEPopup.close();
}
tinyMCEPopup.onInit.add(init);