The application features WBS, Gantt chart, task sheet, resource sheet and. MOOS Project Viewer for Mac OS X v.2.6.2 MOOS Project Viewer is an easy-to-use Microsoft Project viewer that can help you open any Microsoft Project file type (.mpp.Available views: WBS, Gantt chart, task sheet, resource sheet, calendars. xml) for any Microsoft Project version (2000, 2003, 20). MS Project Viewer for Mac v.3.1.3 MOOS Project Viewer is a Microsoft Project viewer that can open any MS Project file type (.mpp.