I've been using creately to diagram -- you can do it over the web that way. Also, 'box' has a pretty good screen record-capture facility.

I'd sit with the user diagramming what they do(if you can't then screen record it). That way -- you make sure they attach the file directly from the point it was generated. -Rule #1: Trust no one.

life.domain.kingdom.phyla.class.order.genus.species...

I use gmail and have personal.l.d.k.p.c.o.g.s and professional.l.d.k.p.c.o.g.s accounts. I keep an account for each of the software technologies I'm interested or proficient and do likewise for personal interests or projects. I have an email address and a SeaMonkey or FireFox profile for each. I set the masterpassword to something familiar for each and let the password remembrel do it's thing. This works for me.