Image displayed on IMAN monitor is full of garbage . A noise spike has gotten into the data stream. The reduction program probably will skip over the bad image and not include it in the average values for the aberrations. If so, and if you get two good images out of a star sequence of three images, that probably is good enough. If not, take another star sequence.
Images continue to be full of garbage.
Turn camera power off, then back on. Restart the IMAN PC starting at step 3.01 above. During star sequence, the message in the blue box on the TCP screen freezes. Then the box should show the reduction results as they are built up. The window with the TCP menu should disappear.