→Writing your own form definitions: not the place for this comment!
* An <code>_attribute</code> element. This contains the key used to store column information in the attributes of event reference objects within the Gramps database (The "Type" Attribute of the reference information for the event. If you use "<code>Name</code>" then the selected person's name will be prefilled. Once defined this text must not be changed.
* An optional <code>_longname</code> element. This contains a fuller description of the column and is only used for tooltips (when you hover the mouse over the field in the form).
* A <code>size</code> element. This contains the size of the column in the census report. It is a percentage of the page width. The sum of all size elements in a definition should total 100%
. I'm unsure whether this works (it didn't for me).