and I don't see my file. If i run /root/myscriptname.sh from the command line it runs fine. I tried using bash /root/myscriptname.sh in crontab but that didn't solve it. How do I execute mono-sgen /root/myapp.exe /path/file > /dev/null 2>&1 without putting it in crontab (I want to leave it in a easy to disable sh file)
Rather then mess with a crontab entry I'd be inclined to put a script together that can be run as part of you logging into your desktop environment (DE). This can then be added as "Startup Programs" via gnome-session-properties.
Isn't it cleaner to put this in rc.local (or equivalent)? It's the standard way of doing things after boot. It's better, because it's not called when cron wakes up (which is in the middle of boot procedure) but after all the services are running. It's also more robust. If you want logging you can still use "logger" command.
Also, the script may have started, but failed after a moment and is thus not seen in ps.