Ok, I think I am getting somewhere now. When I remove the tiff preview option, it works just fine. So it seems like it works if the original doesn't have a -tiff attached to it. (I like the preview for when i import the graphic in a WYSIWYG word processor).
I tried using the script to improve my matlab-generated eps files (created using print('-depsc2','-tiff','-r600','filename.eps'])), but the output file cannot be read by ghostview.
I get the following message "DOS EPS header is bad". Ignoring DSC comments" in GV.
The Adobe Distiller-generated PDF for the eps file is a blank page.
Although, I do think it would be good to put in a warning if tiff preview is activated in the file being processed. It seems that a flaw which removes plot lines would be something of which the user should be made aware (along with the quick solution)!
15 Mar 2012
Improves the style of lines in MATLAB generated eps files
After hours of searching, it would have helped if I scrolled down the page to realize that I simply needed to remove tiff preview. I have no idea why my previous "workaround" worked, but it did. Thanks for your help, works great.