Another gameplay issue / design issue - when you want to upgrade an existing design and not replacing a module that requires special resources - the upgrade option won't display that new ship design unless you have extra of the required resource for the new design even you are not replacing changing that aspect of the original design.

Also had issues at least with Dregnir where their original colonizer design had two colonization modules if you delete the mysterious first module that resultant ship design can be built but is no longer loads colonists and is no longer flagged as a colonizer even though has a colonization module.