There is no update for the XL-5000 Conversion Tool. I've checked the official website and all the available website, but it appears it hasn't been updated in awhile. If you still have the application, right click it and go to Properties > Compatibility. select a previous version from there (Windows 7 and Windows XP) and run it. This is the only way since no update is available.
However, if you lack the application, use the following link and and get in touch with Singer Customer Support: http://www.singerco.com/company
I believe they will give you the necessary instructions and the software to transfer the designs.