iStopMotion won't let me open saved files - help

Hi, I am having a big problem. I have istopmotion on my mac and when i try to open my files it will only work if I go to file then select one of the files showing under open recent. If the files are not shown there and I click on the open tab the program shuts down. I have checked my memory and its ok (I also have an external hard drive) the problem is that I really need one of the files not listed under recent ASAP and I don’t know how to open it - can anyone help me?

What happens if you right click/control click the file in the finder and select “Open with…” > iStopMotion?