I have every version of MAS (v3.71 - 4.4) on server and accessing them is usually not an issue. Rerunning Wksetup is about the only PITA that I have to do occasionally. If you do use a third party app, be sure to launch the correct version of MAS first so there is less confusion with the ODBC driver (it seems to default to the last version of MAS used). Regarding Crystal, I always launch designer first, then find the form to modify via the open command in designer.