Error while trying to edit a thread's cover

[SnickerPuffs]

I wanted to center the images on one of my download's "cover", but when I try to save the changes an error pops up.

Why is this happening?

 

[VEssex]

Gonna bump because I also have the same question.

 

[Geit]

I wanted to center the images on one of my download's "cover", but when I try to save the changes an error pops up.

Why is this happening?

The covers being able to pick up images you upload to a resource (as opposed to being a seperate upload) is a hacky hack I did - you're not supposed to be able to see the edit button, where are you managing to find it?

EDIT
Nevermind - should be fixed and hidden now