Removing a CD from release

[Nisto]

I was browsing through various albums yesterday and I found for example, Perfect Dark Dual CD Soundtrack - and I saw that it said "1 CD" next to media format, so I pressed edit on the album page and entered "2" next to "Add media". The thing is that I was supposed to put 1 in that box...

So is there any "remove CD" button anywhere? Has it even been implemented yet? Would be a good idea if not so.