I don't know about re-coding but if you want better convertible top functioning you can get it, at a price. This isn't the cheapest source I've seen for this but this link specifically references the 1 series:
http://www.pcars.com/porsche_parts/s.../p_185272.html
In addition to allowing operation with the remote, it also allows one tap to open or close the top. I've seen what may be the same thing for $300 from other sources. If you google "smarttop" you can get more information. I saw a video of it installed on a 1 series.
Jim
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128i Convertible, MT, Alpine White, Black Top, Taupe Leatherette, Walnut, Sport
Ordered 5/22/09, Completed 6/4/09, At Port 6/9/09, On the Georgia Highway 6/13/09, Ship Arrived Charleston 6/24/09 at 10pm, PCD 7/21/09
