I disabled VST 2.4 Plug-In Support service, restarted S1, and was able to open the song.
I removed the automation lane, saved the song, enabled the service, restarted S1, and tried to open the song again. No joy.
I ended the task, restarted S1, disabled the service, restarted S1, opened the song, removed the Kontakt track and instrument, saved the song, enabled the service, restarted S1, and was able to load the song now that the Kontakt track and instrument weren't in it.
This is a bummer. Maybe the issue is specific to Evolution Songwriter, but I'm new to S1 and not being able to automate Kontakt parameters is a bit of a showstopper, given how much I use sampled instruments.
Sorry if I hijacked your thread, Gavin. Given that my issue was also a memory issue, I was trying to avoid duplication.
Anyway, with my issue, I don't know whether the fault with with S1, Kontakt, or Evolution Songwriter. I'll report it to all three developers and hope that one of them is able to sort it out.