Just installed tonight. Ended up at some point with this issue; it started auto focusing and no windows popped up, it just said ‘focusing is running’ in the bottom corner. Restarted and seems to work now.
I took a look. It may be due to the issues 2.4.3.8 has with nebulosity rejection values going to MAX for old sequences.
[10/8/2015 9:39:23 PM] [DEBUG] [Camera Thread] HFR value was 0 three times… probably not going to get anything else, continuing…
[10/8/2015 9:39:23 PM] [DEBUG] [Camera Thread] Handling monitoring event (Good Night System, Warning).
[10/8/2015 9:39:23 PM] [DEBUG] [Camera Thread] GNS: Sent warning message to GNS ((IC1396) Auto focus received a bad HFR value 3 times in a row! Something may be wrong!)…
After this, AF seems pretty normal. Getting an HFR of 0 could mean that the smart focus pushed your focus way out of range because the nebulosity rejection was so high.