Hello,
Can you give me some info on how to use a .atn file with Photoshop?
Thanks!

Go to the Action Palette. If the Action is already loaded, just scroll down to it in the list and select it and click the Play button. If it is not loaded but is saved in some folder, click on the little triangle to reveal the context menu. Scroll down and choose "Load Action". Then just navigate to where the action is stored and click ok. Then hit the play button.
Regards, Murray

thank you!

Sorry for jumping in here, but you can also just "drag and drop" the file from a folder into Photoshop, when you've got it running on computer. You don't need to put it in the proper folder, it automatically puts it into the correct place.
John.