Are you using the latest version of X-cart? X-cart 4.4.2 is now available.
There’s a lot of new things introduced in the 4.4 version including an overhaul of the Administration back end of X-Cart. There are some fixes to the UPS and FedEx shipping modules, fixes for the zip codes with more than 5 digits, additional payment gateways added (and some removed/renamed), and one of the biggest things the Add-On modules are now included.
There’s seven Add-On Modules that have now been included in the default source code for X-Cart; X-Affiliate, X-Configurator, X-FeatureComparison, X-GiftRegistry, X-SpecialOffers, X-Magnifier and X-Survey.