OK...from the horses mouth.
Briefly stated, the EU Timber Regulation only applies to timber which has been 'placed on the market' after 3rd March 2013. So any timber you have in stock that pre-dates the regulation will be exempt from it.
'placed on the market' is one of those legalistic euro-speak terms that means very little to most people. Essentially, goods are considered to have been placed on the market once they have cleared customs in the UK/EU and are made available for free circulation.
Taking your surplus timber example, the timber you have now is placed on the market already. Timber can only be placed on the market once, so if you sell this timber after March, it is not placed on the market for a second time. That said, from March you will need to maintain records of any other traders you supply timber to, and the traders in question would need to record who they have purchased the timber from.
So if I understand you correctly then after 3rd March if I sell some of my surplus stock to another cabinet maker (aka trader) then I just need to keep a record ?
Has the level of detail been defined? Is 'Sold - 2m x 50mm x 300mm board of surplus mahogany - to A.N. Other Cabinet Maker on 8th June 2013' sufficient? I may no idea what type of mahogany it is, to be honest.
That sounds fine - as long as you can demonstrate what you have sold and to who, you should be fine. It is important however that you obtain the address of the company in question, so that should we need to, we could visit them too.