How do I reload photos in Topaz Photo AI 2.0?

Given that it appears that Topaz Photo AI uses a cached copy of the image, is it possible to reload the image from its original location?
While viewing old, damaged photos in Topaz Photo AI, I’m using an external program (Gimp) to repair some of the damage. The original, unedited version of the photo appears after I save it from Gimp, close it in Topaz Photo AI, and then open it once again. Topaz Photo AI must be closed and reopened in order to be used.