It sounds like you did not have this problem before with DG. One possibility is that you have two instances of DataGraph running on the same file. For example, you had the file open on another computer and then forget to close that file before moving to a different computer. Or you might have two instances of DataGraph running on your computer (check for two DG two icons in the doc).
Either way. we would recommend updating to the latest Beta. There are some recent changes we made in our saving protocol to better handle when you have two instances open.
In fact, we would be interested in whether the Beta version fixed this issue.
The second thing to check is whether or not One Drive has reverted to using Files on Demand. There was an automatic update that OneDrive had a few months ago that automatically turned on “Files on Demand” for users. That means all your files live on the cloud and are only downloaded when you open them. We had one user with some corrupted files after this conversion. See this older post on One Drive for more details.
We recommend that you do NOT use Files on Demand with DataGraph or at least set DataGraph files/folders to “Always keep on this device”. DataGraph is a package file that is actually a folder. It is a native Mac format and it’s not clear that OneDrive is able to always appropriately handle these files when they live only in the cloud.
Here is a screen shot about OneDrive to help you discern when a file lives in the cloud. See the little cloud icon in the bottom right corner.
The last thing you could do is turn off Autosave, but if you can try these solutions first and let us know the results, we would appreciate that. Thanks!