I'm starting to work on my own theme. I'm having a real hard time with anything other than right angles. Anytime I use curves or circles the transparent image always has a few black dots around it like this.



I use photoshop to create the images and use the following process to get the alpha channel.

-Place all the buttons on one layer
-Select All
-Copy and paste the exact duplicate of the buttons on another layer
-Set saturation to zero, brightness to maximum and contrast to minimum (creating complete white images of the buttons)
-For the transparent layer I usually select only the appropriate alpha channels and change the brightness to the appropriate grey.
-Multiply the alpha channel layer.
-Combine all images and copy and paste it back into Themepark.

This works perfectly for objects with sharp angles but not rounded objects.

What am I doing wrong?