Note that is not for the most recent version of PS. You can connect the tool using a script to install it. Go to the Escape Motions website and go to Flame Painter Pro section and download and then on the right side there is a connect section, download that and then unzip the file. You will see a 1.2.5 and a 1.3.1 or some variation of that, go to the later and you will see the folder containing an installer file (installer.jsx). You need go back to the main application and go to the file and scripts and browse and select the jsx file to run it. Click OK etc and restart Photoshop and hopefully you will now see the feature added. You can then go to the window menu and extensions and you will see the extension added there (in many versions of PS, not all). You can now run it by clicking in the panel and work with the design adding mist / fire etc effects and then bring it back into the Adobe application.
If the extension is not available, simply have both apps running at the same time and save the work via the file and save command and use the PSD format so all the layers etc still remain, it is no point using the FPA format as that is not supported by most applications.