Okay. So here's how I got pictures into a pm.
So, you're in your blank message. Now, there's a little button that says "My Media".
When you click on that. You get this:
Okay, see those three tabs? Attachments, Gallery Albums, and Gallery Images. Any pictures in those tabs you can add to your pm.
So, let's say we click on the Attachments tab. You get something like this:
You can see all the pictures I've previously uploaded to threads and the pictures I tested this on.
Of course, how do you get a picture into this attachments tab?
I just went to a random thread and acted like I was going to make a new post. Click on "More Reply Options".
So now you're here. Attach / upload a photo like you would any other time. You don't have to actually add it to the post or anything. Here, I uploaded this little sheepy.
So then I went an abandoned that post. You won't need it anymore. You can just exit out. I went back to My Media Library (in the pm). If you were in the middle of the message when you decided to add a picture, you'll have to click on attachments to get it to show up. And then poof! There's my sheepy!
Now all you have to do is click on the image. A black bar will pop up, saying that it's been added. And then you can click finished in the bottom left-hand corner.
Now, your message should look something like this:
I added some words, clicked preview, and here's what I had!
There ya go! I hope it helps!