So I just discovered the debug feature in Kentico. My coworker was able to figure out the root cause of the missing Master Page tab. It was due to an error passing a GUID to a macro. This is apparently a common issue while exportin/import. The fix was to run update signature utility.
The inability to edit web parts in the Design tab is still an open issue.
In the debug log, I captured the logs for the simple action of "Clicking on the Design Tab".
The goal is to see what payload gets returned by Kentico, and all the logic that gets executed behind the scene. I compared the destination instance to my localhost (where design tab is working correctly).
Under the Page Output section of Debug:
- In localhost, a request to /getdoc is made which returns the proper Design tab page, including the ability to edit web parts
- In my destination instance, the /getdoc request does not get made. This seems to be key to the problem. I'm not sure what controls are in place to generate the request to getdoc when clicking on the design tab.
In the "All" section of Debug, the execution steps and result of each step look equivalent between the two instances.. No obvious sign of difference in behavior. Argghh