How to set the spawn of the world?

First Sorry for bad english! :S

And sorry if it's in the wrong forum thing

I used MTA Map editor to make a Freeroam server. I used a MTA to SAMP converter: http://convertffs.com/

Works perfectly!

But if I join. I spawn on a platform with escalators.

But I want to spawn in Los Santos Airport.

Help me! Thanks