Given how little of the Tiger's design documentation has survived, the best wartime description of this tank comes from the British Army who examined the captured Tiger "131". But their report contains some errors.
All of the ammunition rounds in the tank's sponsons were facing forward, except for those in the rear right-hand bin. But this British diagram of ammunition doesn't match the tank. It shows the rear left-hand bin (marked X) pointing its contents backwards, which is wrong.
All of the surviving Tigers and all available wartime photos agree on this. The rear left-hand bin had its rounds pointing forwards. This is an extract from a photo of Tiger "131", at the beginning of its 1990s restoration, and we can see that ammunition bin. It is empty, but the solid panel (arrowed) and the two supports that are close together, always take the forward end of the rounds.
Ustar have made the same mistake as the British draftsman in 1943. They point this bin's ammunition the wrong way.
It may prove a simple change to reverse the direction of the shells in the kit. But the wall of the bin is harder to correct. Ustar have put a box on it (arrowed) that never existed, and they have molded the folding doors into the forward end of the wall, whereas they should be at the rear end. To correct it, cut off the rear section with the unwanted box, detach the door section, and insert a new blank section between that and the center slot.