Hi everyone,
The cube test is a real nightmare!
I can recommend a book that I used, it does have examples of cube tests but more helpful is at the end of each sample test, it gives you tips and ideas on how to tackle the various tests.
The book is not just on cubes, it also goes into tests on shapes which are rotated etc, lots of advice and hints.
The book is designed for mechanical spatial tests, and for the first part of the book deals with this, however half way through delves into spatial reasoning tests.
Anyway, the book is " Mechanical Aptitude and Spatial Relations Tests" By Dr Joel Wielsen, the producing company is BARRON'S.
It contains 18 full length tests. I bought it from Amazon for £9.99.
I don't know whether it'll help but it never hurts to try!