What a coincidence...
What a coincidence...
Same problem occurred with my R2A today when I was shooting in the park. At first, camera would shoot as soon as lever was advanced (no pressing of shutter release), then shutter just stuck - gray curtains open, black ones closed.
First thought was that batteries died - so I changed them as soon as I got home. Didn't help - nothing changed. Meter also did not turn on, even though the shutter button was pressable.
So, I took off the bottom plate to check it out - nothing seems out of place.
Next, I tried
this trick - I dislodged the little claw that locks the advance lever, and advanced the camera. Hear a click - the gray curtains close, but they look somewhat weird (not sure, may be just a psychological thing). Here's what things look like:

Click on thumbnails to see full size.
After this, with bottom plate installed, whenever I try advancing, the assembly just slides to the right, then click back to their original positions on the left (obviously, can't see that with plate on, but I'm pretty sure that's what happens). Curtains don't move at all. In addition, if bottom plate is not in place, when at the far right position, assembly gets stuck there - like in picture below. Does not happen when bottom plate is installed.
I'm kind of lost on what to do next..