If you have a project with a bunch of table and view mappings configured, you can easily switch between (similar) databases and retain those mappings. However, if you switch from the database type to the scripts type, even if the schema is basically identical, any mappings with filters get unchecked, but the rest remain selected. RedGate silently makes this change, and it should be considered a bug. Let me choose which action to take. If you try to re-enable those mappings, the filters are only applied to one side of the comparison, which is also an issue.