CDSEO is now compatible with x-cart 4.5.
When upgrading to the x-cart 4.5 branch while using CDSEO, you will be able to maintain all of your SEO urls, titles, meta tags and other SEO information to retain your search engine optimization through the upgrade and ensuring urls remain the same. Just be sure CDSEO is installed on your 4.5 store and bring over the wcm_cdseo* tables when your database is upgraded.
You can upgrade at
http://www.websitecm.com/x-cart-mods/cdseo-pro-x-cart-seo-pro-upgrade.html