I wanted to explain the weeping issue for those who have asked because I had the same problem as the OP. I too have used the same recipe for many years with no problem, a 1/2 margarine and 1/2 shortening...that is, until Crisco changed the recipe.
I always had a firm icing that never separated or leaked oil. I made a dinosaur cake one day with a volcano on it. On the short drive to the delivery, the icing slid down the volcano. I made the kitty pumpkin cake that is in my photos. You can see the oil seeping in this picture. Look at the bottom of the cake where the icing meets the board.
The icing was a dream to work with as usual but on another short car ride, this time with my daughter holding the cake to cushion against any vibration, the icing started to slide down the cake. Not only that but as was previously described, after several hours of sitting, all my cakes had a small pool of clear oil around the base of the cake. I could not figure out what I was doing wrong. I started adding more sugar, cutting back on shortening, making it all shortening (thinking the margarine was the problem). I still had the same problem. I heard about the Crisco recipe change online and realized what was going on.
After hearing everyone's comments, I believe that the new Crisco does make a difference but so does the recipe. Those who use milk, butter or meringue powder don't seem to have as many issues as those of us who have a recipe that uses water and margarine. Now that I add Dream Whip, my icing is more stable but since I still use Crisco, I still have some issues with oil pooling at the base of the icing. I'm not willing to give up the lightness of Crisco for the hi-ratio shortenings just yet.
Here is another example. I'm using the bigger pictures in my album instead of posting them here so you can see them better. Almost identical cakes. This one is made with the old Crisco. See the dull smooth finish.
Look at this cake with the new Crisco. See the sheen and shininess of the icing. That seems to be the oil leaking out.