If a train had stalled it would be REALLY obvious, as if that was the case AT would have had to bring in a crane to lift the stranded car off the tracks (as standard regulation). This, however, seems to be the case of someone from the H&S being a bit disorganized/slow and messing up some of the paper work (or is potentially dissatisfied with a safety aspect of the ride).
It is important to note, as stated above, the ride has been signed off by the manufacturer which means that the operational part of the ride is fully functioning.
Simply, the reason we can't go on The Smiler yet is due to one of the most pure evil devises conjured up by the deepest, darkest parts of the government:
As it is the bank holiday weekend that H&S inspector isn't going to think about looking at those forms again until Tuesday.
"The Marmalisation Process has been scientifically designed to ensure a sense of euphoria and satisfaction should be had by all... There are no, known, Long Term side effects to the Marmalisation process, however short term side effects may include: dizziness, vomiting, loss of balance, loss of limb control, feinting, wild hallucinations but most importantly Smiles!"