I posted a sample project for a user by uploading a zipped project folder. After I made the post I thought of a small change. I could edit the post but saw no way to "edit" the attachment. I was hoping to be able to delete it then upload a new version. I ended up deleting the post (which caused the post to be greyed out, but not the attachment) then posting the same text again with a new attachment. Would it be possible to add a "delete attachment" feature for such an situation?

You have to click Edit on the post, and then go ahead and click on the paperclip in the toolbar the same way you did to add the attachments in the first place to give you the ability to edit/delete attachments. This should work for any post after our migration off of vBulletin. If it doesn't, it's a bug, and let me know.

It works. I can't believe I didn't notice that when I uploaded it.