It does seem that some manufacturers don’t consider details like tank/carburetor relationship. Since the beginning of time the correct relationship (upright or inverted) between carb nozzle and tank has been the same, carb nozzle approximately 1/4” to 3/8” above the tank centerline. Violate the basic principles and most often one ends up constant engine fiddling. While some do get engines to run in adverse tank relationships most will not.

Wonder if the manufacturer has flown the airplane.

Bill