In Winter '17 we are able to include in a managed pacakge a "Lightning App" that pre-defines tabs to include.  From the Lightning App Manager in a subscriber org (where the package is installed) if we edit the app it allows us to remove "Selected Items", but when we go to save the changes we receive the following error:
Is this a platform bug or simply, a limitation, or not yet a supported action?

Thanks,
Ross

Does anyone have a working example of a trigger and class written to implement the TDTM functionality from the HEDA managed package? I have installed the managed package in a dev org, and I am encountering class visibility issues when I try to save the following trigger, which is modeled after the triggers from the unmanaged version of the package (pulled down from GitHub).

trigger TestObject on Attachment (after delete, after insert, after undelete, 
after update, before delete, before insert, before update) {

    hed.TDTM_TriggerHandler handler = new hed.TDTM_TriggerHandler();  
    handler.run(Trigger.isBefore, Trigger.isAfter, Trigger.isInsert, Trigger.isUpdate, Trigger.isDelete, 
        Trigger.isUnDelete, Trigger.new, Trigger.old, Schema.Sobjecttype.Attachment, 
        new hed.TDTM_ObjectDataGateway());
}

I am using the "hed" namespace, which worked when my class needed to extend TDTM_Runnable, but I am seeing an error due to TDTM_TriggerHandler not being visible. Also, if I use my class that extends TDTM_Runnable, I see the same visibility error with TDTM_ObjectDataGateway.

I really don't need a trigger on Attachment. I just wanted to see how simple it would be to get this working. Does anyone have a working example or some insight to share?