Plot hole: When the castle is about to blast off, Brad and Janet abandon Dr. Scott's wheelchair at the door of the castle and carry/drag him across the porch and down the steps. After the blast off, Brad, Janet, and Dr. Scott are on the grass and have been blown some distance apart from each other (in the UK version, there's another song where Brad and Janet crawl toward Dr. Scott so they are blown farther apart than shown in the US version). It seems extremely unlikely that the remains of Dr. Scott's wheelchair just happened to fly from the doorway to land directly under him during the blast. Brad and Janet can barely crawl so they didn't move him or it.
Plot hole: Before "Rose Tint My World" the nude statues of Brad, Janet, Dr. Scott, Columbia, and Rocky are in the same positions, but somehow Frank-N-Furter managed to dress them despite the following impossibilities: 1) All are wearing high-heels despite being frozen while their feet are flat on the ground. 2) The fingerless gloves have a loop through which their index finger protrudes, despite their solid stone fists, except Janet whose stone fingers are solidly entangled in her stone hair. 3) All of Dr. Scott's clothes have been put on him despite being attached to the stone wheelchair and his legs covered with the stone blanket.