I was looking for some information for charities and not for profits this morning when I came across the resources on your website.
I actually just published something called “Guide to advertising charitable status on all written materials” http://www.wrighthassall.co.uk/knowledge/legal-guides/2015/05/19/guide-advertising-charitable-status-all-written-ma/
It might make a good fit for your website. I’d be honoured if you’d consider adding a link to the guide.
Either way, great work!