Jez Then if I manually click the Plate Solving icon it immediately solves the target without an image capture and displays the "Sync Mount & Go To [Target]" message.
ASIAIR plate solve tool has never acquired an image by itself. It has always plate solve whatever is already on the Preview screen (or an image stored in memory).
Acquire an image first, wait for it to finish, then tap on the Plate Solve tool.
If not, ASIAIR is just solving something that was left over, but with the possibility that you have moved the mount's pointing since that old plate was taken. Do not do this, since a subsequent sync will really mess up -- if you are lucky, ASIAIR will just tell you cannot sync because you are too far away from the mount's coordinates. If you are not as lucky, the mount will slew until your instrumentation smashes into the pier.
Chen