The new strace-based copyFile function cp_p() uses a pipeline, so errors can go undetected. Using set -o pipefail seems to fix this.
A separate problem occurs when an error triggers the || clause that uses a subshell to group two commands. An inline command group seems to fix this.
Steps to Reproduce:
1. Force an error in the copyFile function by renaming the source file or provide insufficient space for the copy.
2. Force the use of the cp_p() function by commenting out the gvfs-copy if-block.
3. Execute livecd-iso-to-disk.
Notice that the error does not get trapped and cause the main script to exit.
*** This bug has been marked as a duplicate of bug 663849 ***