Did you try to use CR_INSTALL_INFO::pszSmtpProxy parameter? It allows to define IP address and port for your SMTP server without any code modifications.
About the Date header, I think this may be a deffect in CrashRpt, if some SMTP servers require the presence of Date. I will add the Date header in the next release.
About email attachments.. I do not know why your server recognizes them as text. In my tests, they are recognized correctly. I have no ideas how to help you with this.