Instead of rendering to a audio file (wav, aiff, etc), I'd like to save/record real-time parameter changes to a text file (with timestamp) so they can later be loaded in and playback what was recorded. I'm not sure what the best way to go about this would be. Are there any recommendations?

I imagine each parameter worth saving would have a [change] object after it to see if it's changed and if so it sends the parameter to be saved along with a timestamp that PD could read in and send those parameters in time based on the timestamp. I'm not sure about the playback part and how to send a float/notein based on a timestamp.

Any thought on a clean solution would be great. Maybe it's as simple as using the [change] and [textfile] object?

You might want to look at [qlist].

Maelstorm also made some nice state-saving abstractions that could help...a bit more complex, but could come in handy:

http://puredata.hurleur.com/sujet-5664-state-saving-abstractions

Thank you both. I'll take a look at the abstractions and qlist and see where I can get.