Morning laptoplou
Welcome to the abstruse world of The Listener :)
It's always been difficult (and occasionally impossible) to do the puzzles without a copy of the current BRB (Big Red Book - Chambers Dictionary) - the vocabulary in there is 'quirky' (to be polite) and the setters exploit that.
I'd also say that, as the technological arms race between setters and solvers escalates, it has now become very difficult to do some of the puzzles without an electronic/searchable version of the BRB.
I've got the excellent iPad app, but also the iMac version which is even better (it adds a full text search and some anagram solving capability) - I presume the Windows version is similar.
They all cost (around) a tenner these days and are arguably better value than the £40 printed version - although that is currently £26 on Amazon and I do love real books ...
Dave