After month of struggle with the Plenty Systems API I decided to stop using Plenty as a backend for Spree. Since then, some interesting synchronisation code has been made and I'm releasing it to whom it may concern.
The code is highly experimental and the API will vary (as did in the past) and even break - so probably you'll have to make changes to make it work.
Just throw the models into your models folder and create an initializer plenty.rb:
Plenty.configure do |config|
config.host = 'www.example.com'
config.api_token = 'http://www.example.com$THIS_IS_VERY_SECRET'
end
All code is © 2010, 9elements and is released under the MIT License. Feel free to email us with any questions or feedback.