I am posting this question just to see if there are other people who are not satisfied with this kit. With Geneart we are constantly getting negative results. With Clontech's In-Fusion Advantage or In-fusion HD kits we never had a problem.
We tried using the High Order Assembly Kit from Invitrogen/Life Technologies, to no avail. We wound up having Life Tech make the construct we wanted. Seamless Cloning is really just a Gibson reaction; there are others who make Gibson enzyme mixes that may work better, or you can make your own mix, as there are formulations for it online.