I know there is also a possibility to edit the properties of XmlAttachments via .getatt but this method has some impairments I think.
In my case I wanted to make a sign that shows a Dialog when dclicked - my plan was to use the XmlUse Attachment and in OnSuccess i wanted to make something like "GUMP,shattered stone sign,0/Here is a lot of text about the history of the building this sign is attached to with a secret hint for a quest..." - unlike the XmlSpawner or XmlEdit-Dialog there is no possibility to use a "book-interface" for typing this long string so I have to input it "blind". And there is a low charlimit, too, so I can only input a relative short text.
Sooo...

I thought it would be nice to have either a extra dialog for editing XmlAttachment-Properties .. or even extend the common property-dialog with those nice book-interfaces. I'm sure there are more uses for this, inherently you can edit a part of the string without re-typing everything.
Just my two cents.. what do you think?

-- Anheledir
PS: Happy new year!!