Sounds like you may be using Object Desktop Manager. Save yourself a lot of headache and just download the individual .exe's on your My Downloads page. Same serial number works for activating all the individual apps. Just stash them in a folder & install from there. You won't regret it. Plus you'll have locally stored backups.
You get to the page by clicking on your avatar in the upper right corner after logging in to store.stardock.com using the email address you used to make your purchase, which opens a dropdown list including My Downloads.