The needle does not work upon initial starting and then starts working after the engine has warmed up. Yesterday, the car was parked outside with a temperature of 29 F. It took about 15 miles of driving before the needle moved all-of-a-sudden to normal position. This morning with the car parked in a 50 F garage, it only stuck for a short while.
Yes, I have also had the gas gauge needle stuck(?) in the resting position, but that also comes back if you are a little patient and wait for it.
It could be that the needle is "sticking" to the lower post as you suggested. I will monitor for a while to see how it behaves. I guess the temperature sending unit is working if the gauge eventually rises to normal position.