Unfortunately no details available. The surviving drawing is little more than a quick sketch, one of at least four alternative schemes and the others are all missing.
It is indeed unreasonably cramped for the crew, especially the gunners as you say, and would obviously have been rejected had it been tendered. The real interest lies in its similarity to Boeing projects of that time and the features that were carried forward for the Type 316. It would indeed have been interesting to see a down-scaled derivative.