Where can i Download the Photoshop Generator plugin for reflow?

I'm trying to export a design from photoshop to reflow, but the option is not available i only have generate image assets. I have gone into preferences and enabled generator under plugins but it's still not working. Any suggestions? I watched a few tutorials on it including adobe made ones, they mention a downloadable plugin if it for some reason didn't come with the latest version of reflow/photoshop.