I can't actually offer any help either I'm afraid, I'm answering to bump the topic because it was on our possibles list for backpacking and I'd be interested in any answers. I've never seen a walk report on this trail anywhere, though there is a printed book.
The big problem for me was the (almost certain) difficulty of wild pitching on such a route, it's hard enough on coasts in England and Wales but IOM is a popular tourist oriented island.