When torilauncher is started, it checks for the file toribash_server.exe (case sensitive).
As treacles pointed out, the textbox at the bottom can be copied, since that is a the complete command-line reflecting the options you have chosen.
*doh*
I didn't notice that the server-executable is now tb_server.exe
I will fix it in the next version of Torilauncher. Until then, the server-executable can be renamed without any consequences.