Make back-ups often. This may be weekly, daily or even Lunchtime and evenings. It depends on the level of work being done on the model A general rule is to backup (which also compacts the file) at least once a week, or if the model doubles in size.
Before publishing lock the pages that are included in the issue so that they cannot be accidentally edited. In order to edit a locked diagram you must unlock it, this will record that in the version history (unless you have de-selected the option).
To Lock pages so that they cannot be edited, go to Page details and change the lock status by clicking the Locked check box.
Note - If you change a page lock status, all open diagrams are immediately closed.
In the project details Users tab you can see which pages are locked.
If you change a lock status this is recorded in the project history.
The History view shows the major changes to the model and the issued versions and allows you to go to the compare form where you can see the differences between a previous version and the latest one.
When upgrading a model to the latest structure version, the History also records the details of what was added in the Model version history.
The History form provides simple facilities for maintaining your backups of previous versions of a model. You can delete files from the archive and store a reference to when and what was deleted.
You can from the View History (Issue tab) completely reset the version of all the diagram pages and matrices in a model back to Zero.