FoW British starter force and the 7th Armoured Division – Check My Homework?

So, I have made a start on my first set of historical miniatures in the form of the British Starter Force: Desert Rats Squadron. Now my copy of the D-Day British book has turned up and I am trying to put the models to the history in context of the game’s formations.

I am choosing to focus in the 7th Armoured Division because, as I do not have any real family history of service in the Second World War, my wife is a Northumbrian and I now live in that part of the world so a lot of the units that served either in or with the “Desert Rats” have historical links to the surrounding area. This is the formation I am trying to represent to start with (and maybe dipping into the 50th (Northumbrian) Division for the same reason down the line).

So, now I am trying to sort the tactical flashes out for these units and I think I have a decent idea for most of the units provided in the box. here is what I have.
Cromwell Troops (inc. Fireflies):
7th Armoured Division, 22nd Armoured Brigade, 1st Battalion the Royal Tank Regiment, tactical flash 51 and red squadron marking for seniority.
Stuart Troops:
The same as the Cromwell as I whatever I pick, they would serve the same.
25 Pdr Field Guns:
7th Armoured Division, Divisional Artillery, 3rd Regiment Royal Horse Artillery, no tactical or squadron flashes used.
Universal Carriers:
7th Armoured Division, 22nd Armoured Brigade, 1st Battalion The Rifle Brigade (Motor), tactical flash 54 and green squadron markings.

These are the ones I have some unknown regarding:
Crocodile Churchill Troop:
79th Division, white markings as attached from another Division. Have been unable to determine what their tactical flash would be. Would be one under the 7th Armoured as they where attached or would it be from their own 79th?
M10 Tank Destroyers:
7th Armoured Division, Divisional Artillery, 65th (Suffolk & Norfolk Yeomanry) Anti-Tank Regiment, tactical flash 77. Cannot find photo evidence that these would have used squadron markings. Where they just not used as these are technically artillery and not tanks?
Infantry:
Planning on imagining these as the 1st Battalion The Rifle Brigade (Motor) along with the Carriers. My question here is that the box comes with the figures to create a parachute or an airlanding platoon. From what I can find, no airborne unit served in the 7th Armoured Division (alongside during the Normandy campaign, certainly plausible, but not as a part of). What I am wondering for this (as this only makes up one platoon) is whether the get a Rifle Company box and role this up into three platoons of the Rifles. I have played around with arranging the troops on bases and I have managed to come up with an arrangement that only used one airborne beret and seeing as the rifle company comes with 4 flat capped officers and 8 sculpts that look more like HQ aides than platoon members, I reckon I can get a spare figure and swap.

So, grognards! How am I doing? Any advice for the Crocodiles, the M10s and the infantry?

And if it helps, here is the transfers I currently have to work with.