Yes, we have used this type of feeder extensively, but not in freezing weather. One solution would be to take the flap completely off the feeder. The primary reasons for the flap are to keep other waterfowl, i.e., ducks, geese etc., from accessing the food or keeping rain out. Other waterfowl should not be an issue at this time, so freezing rain would be your main issue. Pam or any other type solution will still freeze. By removing the flap, you will need to change the feed and clean the feeder more often which is not only messy, but more labor intensive. Another option would be to to try another feeding system, but even then, if you used a pan or pail attached to the dock, freezing /water would still be a problem. Dumping food in the water once a day may be an option, but this would mean that the swans may not get enough food if fish or other wildlife eat with the birds. Sorry we could not be of more assistance, but freezing rain offers few solutions. The Regal Swan