Is "Get Image" the script that doesn't work for you? You've only posted the master script here that calls it.
Without seeing the individual scripts, the only thing I can think to check is to compare the Get Title and Get Image scripts. Does "Get Title" change layouts? If it does, it might leave the next script with the wrong 'context' to function correctly--but I'd also expect that to be obvious in the debugger.
Other issues to check is that when you run a script in the debugger, sometimes screens update a bit differently from when it's not run in the debugger, see if a commit records or a 1 second pause after Get ( Title) makes any difference to the funciton of your script.
I think your layout trouble shooting worked for me. I remembered that I had made the get image script in another layout that was part of the same table. I didn't think it mattered if it was part of the same table but a different layout.