The solution provided in the ticket above is geared toward server admins running RC as a service. What about folks like us whose email is hosted by a web provider, and RC is the webmail application they offer?
Bottom line is, I can literally copy/paste a .jpg directly into the signature block HTML window. When I send an email to myself, and view the email in RC, I see the graphic. When I send the email to my Hotmail, Yahoo, or even to myself and view it in Outlook (via IMAP), the graphic cannot be seen, no matter what security stuff is disabled (add sender to safelist, "Show attachments", etc).
When we used the same address, but another email provider (SmugMugDomains; a reseller of GoDaddy services), there were no issues. In the siggy block formatting window (which is HTML-powered), there was a button just for uploading small graphic files for inclusion. Why wouldn't RC do the same in the latest build? Seems relatively common and simple...