Intelliys supports data exchange with MS Project via .mpp, .mpx files.
Reading a .mpp or .mpx file Use the menu option File Import .mpp/.mpx file . You may select either files with the .mpp extension or the .mpx extension. The imported projects will be installed as subprojects of the topmost project.
Writing a .mpx file Use the menu option File Export .mpx file . Intellisys only writes out projects in .mpx format. This format can be read by MS Project. Note that only the currently selected projects are exported.