I've noticed with this new forum design a "feature" in the Manage Attachments tool called "Insert Inline." This button is really messed up and messes up most of the posts when used. May I suggest NOT pressing that button and your images will still appear, but in a nice block of pics and not spread haphazardly throughout the post. So just load images and when you have them all posted in the section below, press ONLY the Done button.

I have noticed that this tool also tends to forget you uploaded images (not sure why) and if you press Done, and then go back into the Manage Attachments tool they'll be there and you can press Done again - and then submit your message. Just avoid the Insert Inline button like the plague.