Xthreads Spam Prevention

[MasterZuFu]

I'm trying to add a field to a specific forum on my board that allows guest posting. I would like for it to be able to let bots post their email addresses and then display them on the showthread, but only in this one forum.

I have noticed that spam bots are unable to make posts in my forum that also allows guest posting which uses the Trading app, most likely because they don't know how to fill it in and therefore can't.

Can someone walk me through how to do this? Most of my work with xthreads has been with applications on the application list and just running through the steps and tweaking what I need to. This is totally different for me but I'm sure it's quite simple. Any help would be greatly appreciated.