The customer reports and I've verified that there is a "subtle" difference in fts_4500.xps, see sreenshot.png. Command line: xpshead -sDEVICE=png16m -o test_%d.png ./fts_45xx.xps
Another white space issue. Should have this resolved shortly.
Fixed with http://git.ghostscript.com/?p=ghostpdl.git;a=commit;h=91dc74950f0a9ce391de0f0f1f0be5220a68db04. The manner in which sscanf is used to scan the floating point values was fraught with issues when white spaces were present.