Crab Rangoon: keeping the creamy filling

I suspect your problem is being caused by the powdered sugar I am assuming you use to sweeten the filling. The sugar mixes with the moisture in the cream cheese and liquifies. Then it can either leak out during the frying or be absorbed by the dough. You might try adding in a tablespoon or two of plain cornstarch to the filling before using it to counter this. For frying, you need to have at least 3 inches of hot oil and it should be at least 350F- preferably 375F. You should fry just a few at a time, so they have room to float and swim, and don't drop the temperature of the oil when added below the 350F point. Once you remove a batch, let the temperature recover to the correct range. When you are adding in a new batch to fry, add just a few and watch the temperature. It will drop slightly, and then recover quickly if you don't overload it by adding a lot of wontons too fast. As far as a creamy filling goes, be sure you use a full fat version of cream cheese, and not one with reduced fat. Fat means creamy. Low fat versions don't heat well. And make sure your crabmeat is also well drained before it gets mixed in.