Lplex

I have same prob.
When try to create a audio DVD from 96/24 flac files, Lplex start to format the files, but at the end of the format audio process
alerting with an unexpected error:
"ERR: Mplex failed. See Lplex.log for details."

for instance the lplex.log file is in the path specified on the .ini file.
This is the extract relatively at the mplex error:
----------------------------------- MPLEX -------------------------------------

STAT: Running command : "C:\Program Files\lplex-0.3\bin\mplex" -f 8 -L 96000:2:24 -o "C:\DOCUME~1\Domenico\LOCALS~1\Temp\Miles Davis - Kind Of Blue [CR 200g][24-96]_DVD\Miles Davis - Kind Of Blue [CR 200g][24-96]_DVD_title_01-00.mpg" "C:\DOCUME~1\Domenico\LOCALS~1\Temp\Miles Davis - Kind Of Blue [CR 200g][24-96]_DVD\Miles Davis - Kind Of Blue [CR 200g][24-96]_DVD_title_01-00.m2v" "C:\DOCUME~1\Domenico\LOCALS~1\Temp\Miles Davis - Kind Of Blue [CR 200g][24-96]_DVD\Miles Davis - Kind Of Blue [CR 200g][24-96]_DVD_title_01-00.lpcm"
'C:\Program' is not recognized as an internal or external command,
operable program or batch file.
*ERR: Process exit code=1

*ERR: mplex failed. See Lplex.log for details.

any ideas?