Hi guys - It's been a year of happy motoring since my DSG woes. I bought my '08 Mk5 GTI from a local garage and had exactly the same problems with jerky 1st and reverse - made the car undriveable. After taking it back to the dealer, who was helpful, and then several garages, no-one seemed to know what the issue was (suggested oil changes, clutch packs etc). I wasn't convinced as everyone gave a different answer.
Luckily I stumbled across Slater's garage in Nottingham on t'internet. They were very helpful on the phone and are extremely knowledgable about DSG transmissions - more so than VW. They are really enthusiastic about the DSG gearboxes and love taking them apart. My problem was with the Mechatronic unit, despite all diagnostics being normal. I've done 10,000 miles since and the gearbox has not skipped a shift or given me any problems. Luckily my repairs were covered under the warranty I was given with the car.
If you need an answer as to what the problem really is then I would highly recommend these guys in Nottingham. It was over 2 hours away from me, but well worth the excellent service. These guys are absolutely great.