It does sound as if the crank has shifted out of alignment. The rear main shaft and clutch may be skewed, such that releasing the clutch enables you to kick it over, but the clutch plate and spline are still binding due to the misalignment. Try slacking off the cap head screws holding the trans to the engine to see if it will free up.
The press fit of the post war cranks is a fiddly thing. It needs about 0.002" interference, which is hard to press up square without permanently stretching the eye and ruining the fit. Factory refurbished cranks were honed and pressed up with a 0.004" oversize crank pin. Apparently they felt the cranks were only good for one press assembly per fitting.
The post war Dougies will solider on with ruined crank pins, as I personally found out. They just feel rough, as if you had too much ignition advance. Even to the extent where the rod is so tight it will support the weight of the piston.
-Doug