DecisionsFirst Modeler has a number of completeness and correctness checks. Some of these are errors - things that are never a good idea in a finished decision definition – and some are warnings – things that are unlikely to be a good idea but that sometimes don't matter in a specific situation.
In the settings for your account, you can decide when to enforce each of the completeness and correctness checks defined in DecisionsFirst Modeler. Once you have assigned a check to a status level it will be enforced on any decision that is in that status level of a higher one. When a Decision is edited or its status is changed, DecisionsFirst Modeler will enforce the relevant checks and tell you how many problems you have with the decision. If you have warnings or errors you can browse through the fields to see what's wrong and fix it.
Here you can see what happens when there is an error on a decision – the field is highlighted in red and error text is displayed when you mouse over the field. Once you correct the problem the error will go away. Warnings work similarly but have a different color. Here you can see a warning being applied. Just as for errors, the warning will go away when you make an edit to correct the problem.
Note that some errors and warnings relate to multiple elements of the definition – they are comparing two associations for instance. These will count as one error or warning but will display multiple times in the user interface.
Remember, if you don't like the warnings or errors you can always turn them off or specify a special status level at which to apply them.