As I mentioned before, the area marked 'main cb updraught' is the main updraught of the cell. That was so solid it didn't look like an anvil, it's the calvus species (I said capillatus earlier but I was mixed up) of cb. They look more like slabs of concrete or towers instead of the classic anvil. There is no anvil but it's still a cb, I never said the grey cloud was an anvil. The main updraught flattened out at the exact same height (it is already made of ice when the image was taken) so that is the position of the tropopause. The image shows a cb very much in the same way as your nice images show. Here's another example...
These are of a thunderstorm last year, there was no anvil on this storm but instead a bunch of towers, although glaciation was well developed. It technically becomes a CB when the cell begins to glaciate and becomes inflow and outflow balanced. The cell on the very first image (annotated one) was glaciating and producing hail from it's flanks and below. It was was both inflow and outflow balanced and hence a cb and no longer just a group of updraughts, although admitidly a very joung cb. I watched the tower eventually flatten a little further and become outflow dominant with hail before the updraught finally blew it's top. If it wasn't a cb it would be an updraught only and it clearly isn't that on the image.
Here's info on the Cb calvus species...
http://en.wikipedia.org/wiki/Cumulonimbus_calvusThose are nice photos you took. I like the 2nd one with the billowing tops of the towers.