When I open a jpg file on my desktop selected with "choose file" inside an Image Events tell block, the open command is successful. If I set the file reference to a file path, "Macintosh HD:Users:MyName:Desktop:myfile.jpg" I get a file not found error. I am using the (2nd code) example found here.
When inspecting the file reference "this_file" (from the 2nd example on the example) SD shows it as an alias. I tried using "as alias" but AS returns a "file - - - wasn't found" error.