From what I see, you need a bubble box or something to contain the overflow. On mine I just siliconed a piece of glass diagonally in the back corner. It's about an 1-1/2" from the bottom so the water flows under it. Also, I only see one baffle between the overflow area and the pump. Maybe you could install another baffle so that the water passes over the first baffle and then under the next one. That way any bubbles that do get by the bubble box with still be caught by the second baffle. Place them about 1-1/2" to 2" apart. And as mentioned before, shorten your pipe going into the sump. Mine is about 3" under the water.
HTH