The Synonym exercise has certainly been in the exam for the last 2 years as well as the audio test comprehension. However i know that the Univ of Durham (who set the test) do consider changing it from year to year.
VR and Word skills are very important as the KE information states that successful candidates need to have reading and vocabulary skills aimed at age 14+
I would suggest try the new Tutors online Vocabulary material on this site. I haven't used it myself (as it wasn't around when my son did the test) but it is the sort of thing I was looking for (but couldn't find!)
The link is http://www.elevenplusexams.co.uk/cd/the-tutors-vocabulary-builder-volume-1.php
Hope this helps