There goes the profit on that job...
Sometimes if the x gap and Y gap make the image bigger and cut off the graphic's edge. This sizing thing seems to be a limitation in SignLab Flexi and Omega. In omega the taking the weed border off (unchecking it ) and going to layout >border in gsplot and setting it to zero helps.
This is where the WYSIWYG feature in the new SignLab7 should help a person avoid this. Every new software is going to have some weak spots.