An unknown dimension? Are you talking about string theory? I'm sorry, but I'm not a physicist.

Did you switch off all options that delete files automatically (after joining or extracting files)?

You know that there are two options for deleting? One for deleting links and one for deleting the links as well?

Did you override the default download folder by setting a Save to path for individual packages? Check these first by opening the Priorities panes for these packages.

If all this doesn't help I suggest that you try to reproduce the behaviour you discovered and provide a detailed log for examination by the developers.

Here are instructions for logging :-

1) Set logging level to ALL in Settings -> Basics -> General -> Logging.
2) Perform the actions that lead to the problem.
3) You'll find the log tab in ? -> Show log.
4) Click Upload log and post the URL here.