Was MLU enabled? C1 can't fire the camera when MLU is on.
That's usually my issue in this case.
Yes, that was it!
Thank you all, I'll try Breeze, too.
For now, I'm not giving up from MLU for still life studio work, no way. Taking picture with a click of a mouse is somehow strange, anyway. I'm used to taking pictures from camera position, aren't we all?