It sounds like you're looking for the button in the upper-right corner of the SD3 window, correct?
If so, it's still there, but it's different now. It's located to the right of the ACT Learn button and to the left of the S (Solo) button.
You can choose a default editor for MIDI track of the synth by clicking and holding the left mouse button over the button. Then just click the button to launch the selected editor.
Scott
--
Scott R. Garrigus -
http://garrigus.com * Author of the Cakewalk Sonar and Sony Sound Forge Power book series:
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