Today I installed the second box of our Flow Hive, as my wife and I were noticing 'crowding' outside the front of the original hive. Suffice to say, the bees needed it! They had built so much honeycomb that they had built up and out of the inner cover.
Removing the inner cover was difficult in its own right; the bees had built a number of honeycomb connections from their brood frames to the cover. Separating the cover took delicate, methodical movements to as minimize disturbing the bees and to prevent as many casualties as possible.
I opted not to use the queen excluder, but may change my mind after speaking with other beekeepers. Our original NUC provider mentioned that excluders can harm drone's wings when passing between the brood and super.
Overall, the experience was a success and I'm very pleased with the results. We'll see how the bees take to their new expanded hive!