I've been trying to have my ER-1 drum machine controlled by pd for a while and always failed at properly parsing NRPN messages using existing abstractions (I'm on winXP), so I decided to try to find a way to do this by myself. The attached abstraction is the result of this learning process. It is designed to control all the parameters of the first synth part of the machine, it can easily be modified to control any other part (synth or sample) using the Er-1's midi documentation (or any midi monitoring application).
the cool part of this is that it extends the sonic capabilities of this extraordinary little piece of gear by making you able to automate several parameters when the machine's inner automation system can only remember changes for one parameter. When I'm done with building one abstraction like this for all the parts, I should be able to lay down some pretty freaky rythm sequences (!).
Please feel free to use it if you own an ER-1 and let me know what you think of this.