Full details of the candidacy requirements are available on the website.
The problem I've found with having a mental health condition is, regardless of the Disability Discrimination Act (UK) or the Americans with Disabilities Act (US) is employers can still discriminate against you indirectly. Sure, you may be "overqualified" or "someone better came along", but the fact of the matter is employers can and do still discriminate. I've been there; it's not fair but life isn't fair.
(I hate saying "disabled"; just because we are less-abled in some areas doesn't mean we can't excel in others. Well, at least Google agree.)