The stand is designed to support the model completely, so it doesn't suffer sag or has any impact from standing on it's wheels for too long. The model locks in on two of the 5x7 frames on the bottom, so it doesn't slide off and is held securely enough.
Please note, that the finished model may have a little bend on the base. This is not noticable when the Porsche is on top.
The LDD file has separated sections that should make it easy to assemble the stand.