HotRod said:

Regarding the existing hologram of Vader, something I've always wondered (well not always as I do have a life) But does that mean on Vader's ship, he's looking at a giant Veers, with Vader looking up at him, with Veers looking down...A little like Vader and Papls holo scene...If so, bit odd isn't it???

I see no problem here, the AT-AT´s cockpit is quite small, we don´t expect to find a big holographic platform in there like the one Vader talks to the Emperor. We also don´t know how big Veers apears to Vader on the Executor, assuming he appears at all... :) Also, Vader is not as megalomaniac as the Emperor, I doubt he cares how big he appears to his men on communications as long as they do their job... because if they don´t... well, Adm. Ozzel comes to mind... ;) And Ozzel surely did appear bigger than Vader on their short chat which only served to give Vader (and us) a HD look on Ozzel´s demise... :)