;D Certainly sir!
the direction of the "pull" can be changed by the positioning of the cups on the chest.
To get the pull to come up from the under boob the best position for your body to be in is horizontal on your back, allow the cups to touch in the middle point of the chest and get the cups to a point where they have enough suction to stay where they are then position them so that the cup rides up the under boob about an inch or so...if possible pump with your arms over your head, if you cant do that without the cups farting move your arms down and pump till that point is in the cups then resume pumping with arms completely over your head. If your chest does not slope down toward your chin very much in this position you can place a pillow or other item under the small of your back to cause more downward slope. If you can manage it, you can also apply pressure to the cup along the area you dont want to pull. The side NOT recieving the pressure will pull in first and you can FORCE the pull if you want in this way.
Pumping them on while bent over is easier...but you will notice it tends to pull from the top of the breast, play with how you put the cups on to see which part gets pulled most and you will get the idea. To create more cleavage, start with the cups as widely placed as possible instead of touching in the middle. Get the idea?
Personally I think the domes should be made in a more natural breast shape with a tear drop pattern at the opening but I have never had something like that to test yet.