Files with CMX extension are Corel Exchange image file format (also known as Corel Metafile Exchange) that is used as presentation by CorelSuite applications. It contains image data as vector graphics as well as metadata that describes the image. CMX files can be opened by CorelDraw, Corel Presentations, Paint Shop Pro and some versions of Adobe Illustrator. CMX files can be converted to other formats such as JPG and EPS.
Files with .XLT extension are template files created with Microsoft Excel which is a spreadsheet application which comes as part of Microsoft Office suite. Microsoft Office 97-2003 supported creating new XLT files as well as opening these. The latest version of Excel is still capable of opening these old format template files. Such a template file is used to quickly create new Excel files with default data and settings such as page formatting, font size, margins, charts, etc which can be further saved as new .XLS files.
You can also convert CMX into many other file formats. Please see the complete list below.