Hi @jawynan1, this exactly was I am looking for since ages. May I ask where you put the bp-custom-php file? I just registered within the site you are mentioning here, but I cant find the function to create a direkt message nor do I see a button on the listings page.
It would be so much help for me, if you could give me a quick step by step overview. Just some info where you put the code above and if there is something else to modify.
Also, may I ask what theme you are using? Looks like Listify, am I right?