Since screens are wider than they are high, I rotated the room 90 degrees so that I could fit the room comfortably on the screen. I'm trying to make a 3d sound render engine based on the same HRTF data you used. I am using the compact package, with white noise to test. The results are bad, I can't hear a source comming from a certain point in space. That is why I augmented the spatialization cues using commmon mode information.
Reverberation helps to externalize the sound.
Without it, the sound appears to come from inside your head. Reverberation definitely helps, but you have to make a trade-off between the externalization and the fact that the extra reflected rays can diminish the accuracy of the perception of direction. The HRTF based filters you use for the reflected rays must correspond to the direction of arrival of the ray. The overall project was to test the practicality of an enhanced communications system for military applications. The sample rate was chosen to be comparable with existing communications links.