This behavior tree task is not making my AI character move to a random point on the navmesh like it's supposed to, any idea why?

The problem seems to be your Wander to Point BTT, see this one and do the same and try, it will work:

Thanks very much. I tried replicating your BP but it still doesn’t work. Here’s a screenshot, did I miss anything?

http://i.imgur.com/WqaLoO5.jpg

Hello

I really think that the “custom event” node is not what you should use

Use the event: “Event Receive Execute Ai”

Now it shoud work!

It worked, thanks!

Great! I apreciate if you could finish this question accepting my answer!

Good luck!