you might try creating a temporary globalfield, gTemp, then right after the print step in your script place the following:

SetField ["gTemp","Status(CurrentError)"]

then place the gTemp field on a layout somewhere and then run your script.if fmp is generating an error it will show up in this field. if there is you can use this error number to control what happens in your script, with a conditional script step, when you encounter the error.

At the moment, I'm using a HP 4L...I tried setting Error Capture On, but it doesn't seem that Filemaker passes the error (out of paper for example) back to the script that is running. I've got a layout that has a print button on it, which when clicked transfers to a duplicate layout without buttons and without color. The script then calls Print. If the printer has a problem, I am stuck on this second layout, without any error message(s) and no way back into the contolled environment, eg stuck on a layout without a 'return' button or message. What do I do then?