I'm very keen to get this finished now with someone's kind help. I have 4 clues left, interlinked.
24a Concerned about railway providing freight service (8) ?a???i??
21d Ancient king having no trouble heading north across part of Africa (9)
P???a?i??
I'll try and do the other two once I've these answers. Many thanks.
Thank you so much everyone, I assume the other 2 are 25d Fix top of heavy piece of furniture, easily mendable - rightable -, and 38a Getting into trouble,secure some money -banknote. Can't see the getting into trouble bit.