Hi,
It looks like there's probably a typo in one of the XML files you updated. Can you look at line 118 of each of the files (env_run.xml and env_mach_pes.xml) to see if there's a missing end tag (something a missing ">" or something?).
If you can't figure out what's wrong, I'd recommend starting from scratch on your case and only updating XML variables via the "./xmlchange" command (rather than modifying the files directly). This will prevent accidental deletions/additions when editing the file and will also ensure you choose valid values.
For example, here's how you might update to run for 2 days:
./xmlchange STOP_N=2
./xmlchange STOP_OPTION=ndays
Hope that helps!
Courtney