Convert a soft synth midi track to an audio track?

I must have powered my brain up in dumb mode because I can't figure out how to render a soft synth track as a regular audio track. It seems as though it should be a simple thing to do, but two hours of forum searches and help menu searches has only taken me as far as freezing the track.
 
I have a True Pianos track that is triggered by a midi track that I have applied the freeze function to. That had given me the blue "audio" track that almost behaves as a regular audio track, like a vocal track or bass guitar track. The trouble is that I can't apply any audio effects to the frozen track. This leads me to assume that I've missed a step where I must convert the frozen soft synth "audio" track to a standard audio track.  Is that correct, and if so, how do I turn the frozen track into an audio track? I've attempted recording the frozen track to an audio track, but that hasn't worked after trying various routing configurations. What's the right way of doing this?
 
Thanks in advance. 

Alternatively in Freeze options (tight click on Freeze button) uncheck the apply fx box and they will not be applied to the frozen audio and you can tweak away as much as you like afterwards.