Are there any plans for a new version of ProAnimator? One that uses the nice, new interface which the FX version has? I've been avoiding ProAnimator for the past year because I have major issues with the current interface. But I've recently realized how great this plugin is. It would be even greater if it looked like the FX version though.
The next version of ProAnimator is under development. One of the new features, as you've mentioned is the use of the new ProAnimator FX interface. We don't have a set release schedule for the new version as of now, but we'll post more information when the product approaches release.
If you are having issues with ProAnimator running within After Effects, check if you have an undocked panel in After Effects. Save your current workspace, and select the "Effects" workspace. Then, select the "Reset Effects" command. Resetting the Effects workspace will dock all the panels and you should be able to run ProAnimator without any issues.
If you like to work with undocked panels in After Effects, you can switch to the Effects workspace before you go into the ProAnimator interface, and switch back to your saved workspace after you are finished editing in ProAnimator.