Factorio dedicated server on FreeNAS

I want to set up a dedicated, headless, Factorio server on my FreeNAS machine. It should be simple... but I can't get it to work.

When I try to run the Factorio binary I either get:
Permission denied
or
Exec format error. Binary file not executable.

Im running FreeNAS 9.10 - STABLE and the Jail is running FreeBSD 10.3