I think the answer to clue 30 is "shunter" even though it gives the number of letters in the clue as 6, shunter has 7, maybe an error in the quiz, what does anyone else think?
Thinking about it, another possibility is banker (a locomotive used as a second one on steep gradients, not uncommon in days of steam, e.g. at the climb up to Shap)
I've worked on the railways. 'Shunter' was the only answer that I could come up with too. (I've just googled synonyms for 'shunter' and none of them help).