EXP+ is an Expanded design, which includes an additional .INF file. The .INF file provides color data for the design. If a .BMP file is also included, it contains an image of the design. EXP+ is created with Bernina embroidery software or OESD Explorations software.
DesignShop 12 has the ability to utilize the INF color file data included with EXP+. To save a design as EXP+ in DesignShop 12, check the "Save Colors To INF File" option: