Flight Planning is very easy, or at least I found it so - it's more a time management exam!!. Most of the answers are in your Jepps manual and the calculations are very easy. ie. basic time/distance/speed calcs and PNRs etc etc
Don't bother with Compass Co-efficiants A,B & C in Nav Gen - apparently they've never appeared in any JAA Nav exam yet & only 1 Radial Error Rate calculation has ever appeared. But do know basic magnetism theory very well. All the plotting questions are based on Southern Ireland so learn your map in your Jepps manual as you can take this into the exam now..
MET was the one I didn't like...key areas were High/low level winds, Adiabatics and stability, Thunderstorms & TRS, with climatology know your tradewinds etc etc..
See if you can get hold of Oxfords Air Law feedback cos it's all you really need..that goes for there Ops Proc. feedback too..
Radio Nav isn't really a problem. Don't bother learning Decca and these are the only questions the CAA have on Loran :
Q/ LORAN C is available:
A/ In designated ares
Q/ Frequencies used by LORAN C is:
A/ 90 - 110KHz
Q/ The Principle of operation of LORAN C:
A/ Differential range by pulse technique.
Best of luck.!!!