Angle option affects the direction of the fill. It's not available for Radial though. Edge Pad affects the smooth mixing of two color and continuous gradation.
1. Open Corel DRAW. Draw rectangle. Keep it selected.
2. Click "Fountain Fill Dialog" from Fill Tool. Select "Square" fill type and also select Red color for "From" and Yellow for "To" under color blend. Keep midpoint value 50.
3. In the option, change angle to 45.
4. You can observe change in the fill. It rotates.
6.Try Linear and Conical types with different angle values. Please do not change any other settings.
5. Go back to the first step where we have plain rectangle. Select "Linear" fill type and also select Red color for "From" and Yellow for "To" under color blend. Keep midpoint value 50. Keep default angle value 0.
6. In the option, change Edge Pad to 49 (It's a max value).
7. You get two distinct colors, Red and Yellow in the fill.
8. As you go on decreasing the value, you get smooth gradation. At 0, you get the uniform fill of the two properly blend colors. Please do not change any other settings.