If you see the error, "exec: vtclsh: not found" while attempting to run a script from within a cron job, it is likely because the PATH is not properly set in the cron job. See the following example:

/path-to-rtda/version/hostOS/scripts/ftlm_lmproject: line 16: exec: vtclsh: not found

A regular cron job has a very restricted PATH when it is run. You will need to run it in a shell that has sourced 

/path-to-rtda/version/common/etc/vovrc.sh

You can run it within the setup provided by the 'vovcrontab' command, which takes care of setting up the environment.