Update: Framer Photoshop extension progress.
It has been taking me longer than expected to finish the new Framer Photoshop exporter, but for good reasons.
I was originally going to make a Mac app that talks to Photoshop. Instead, I'm now making a proper Photoshop extension that is always available from within Photoshop itself. Windows support should now be easier.
One advantage of this approach is that the getting started process is a lot easier. Simply double-click the zxp file and install with Adobe Extension Manager. Then when you relaunch Photoshop you can use it immediately. No need to manually activate anything in the prefs or remember to launch a separate app.
I plan to open source the core extension as a separate boilerplate project so that anyone can make a Photoshop extension with a node.js backend and an HTML5 frontend in about 5 minutes. The Framer extension is just the first of many.