>Is it really just the simple String I see in my HANA Repository View?
Yes it is.
>Does the AWS HANA Dev Edition support this new feature?
It should. The release level is Rev 70. Make sure that you have developer_mode set to true. However I believe that is now the default setting in the developer center image.
>Is there something else I missed?
I don't think so. However the errors you listed don't seem related to inactive mode. The UI5 errors. What exactly are you testing? Did you not see these errors for UI5 libraries before you tested in inactive mode?