I like the general idea of having two separate frames. That’s interesting, and I can see how it definitely gives you maximum control over where the text sits. However, in my experience, using Vertical Justification (in Text Frame Options) and Horizontal alignment in non-rectangular text frames works far better in InDesign than it used to. Have you tried that?

And an alternative to ESRI is Avenza:

The Cartographic Standard

We also have this Powerpoint Maps Template here:

PowerPoint Maps Template

Grayed out? You literally can’t click it? That’s odd. I can’t think of what setting would disable that.
Perhaps reset your preferences?

Rebuilding InDesign Preferences

Are you talking about drop shadows that are in the main file, or the placed file.

That is, let’s say you’re placing File A into File B. Is the shadow on an object in File A or B?