Steve, the viewfinder is quite nice and focusing is on par with a normal Moskva/Super Ikonta. The shutter button is indeed squeezed between the rewind knob and the viewfinder cover, so it is no very easy to reach. but it's usable with a little practice.
Yes, Paul, the job is very nicely done. The combined window is on the left.
Michael, thanks for the explanation about Kulibin, ROTFL. This particular A.Kulibin (please note that this is not Ivan, maybe his brother

) seems particularly gifted anyway, as the modification is superbly done.
Cheers,
Abbazz