Brandon R Brooks However, pressing the space bar twice allowed me to bring up CommandUI
Do you mean Shift? Shift+Shift is the secondary way for opening; space+space would be news to me.
Option+k should work fine; what I assume is happening is, Etch is bound to both option + k and cmd+k?
Just to quickly test this, you could try some other key, like cmd+y, or something?
Brandon R Brooks Can I set it up where the default shortcut is Option K so it doesn't interfere with my Etch sites and so I don't have to change the settings every time?
That's not easily possible right now, since the settings are actually stored in your browser, per site, and not globally in CommandUI/WordPress. The preferences/settings are per user, not global right now.
Regarding integration with Etch, what would you expect? Should CommandUI prevent Etch's cmd+k, or?