As well as being nominated by a company you will also need an instructor rating (unlike the old days when you could just be a company TRE) and may therefore need to take a TRI course first, unless you hold an FI already.
When deciding on FE's I know that as well as experioence the CAA also look at geographical requirements and so if there is already a couple of testers in your area they will not appoint any more before someone retires to make space. Not sure if they apply this test to TRE's
Mike and Leon at Helicopter services will see you right and make sure you know what is needed. Have to say now days the emphasis is on making sure that you get everything in order and have covered your butt against a Reg 6 appeal should you fail someone. The flying side is important but you do end up feeling if maybe it is second to the paperwork
With ammendment 4 to JAR FCL2 there is a heap load of new grey areas so you really need to talk to someone who knows what is going on and sadly at the moment there doesn't seem to be anyone especially at the Belgrano who does.
Good luck
Banjo