The AUI code is controlling the Collections functionality.
The popup button opens the modal being disabled
The popup button keeps enabled when changing subtype
The Order By field keeps the options of the previous Item Type
The Save Button is enabled when you select an asset without a subtype for the first time
Sorting options don't appear when you save a collection
Move code from asset/asset-publisher-web/src/main/resources/META-INF/resources/configuration/source.jsp