Last night running 2.6.0.25 I got the following error running the auto focus routine:
The first couple of focus runs ran fine, then this message started appearing on every image capture during the focus process. After clicking OK after each image capture, it would continue to the next image. Otherwise the auto focus routine did its thing correctly and after it finished it continued with image capture just fine, until the next focus process. I ended up disabling auto-focus for the rest of the night.
I have only seen this last night. However, an earlier night with version 25 I had it hang during display of an image during image download.
I am using an ASI 1600mm-c camera.