User Menus editable via Studio (V5)?

[tokyotumbleweed]

I am using the Japanese localized version of SugarCRM 5.0. The Japanese application requires two entries for the same piece of information due to characteristics of the Japanese language. For example, the name of a person is generally written with Chinese characters (kanji). However, to clarify the pronunciation of name, which can vary, the name needs to be also written in furikana, which is a syllabic way of writing the language.
Studio makes it easy to add these extra input areas to existing modules displayed when Studio is opened. But I have been unable to find a way to add these to the User menus (sugarCRM users) through Studio.
Can the User Module (if it exists) be edited via Studio, and if so, what are the steps?
If not, am I correct in assuming that I will have to edit core areas of sugarCRM?
Thanks
Jim