Me contesto a mí mismo: "Fácil"
SMTP_PORT 465
SMTPClient.Server.szROM = (ROM BYTE*)"smtp.gmail.com";
SMTPClient.Username.szROM = (ROM BYTE*)"xxxxxxx@gmail.com";
SMTPClient.Password.szROM = (ROM BYTE*)"********";
SMTPClient.To.szRAM = RAMStringTo;
SMTPClient.From.szROM = (ROM BYTE*)"\"Servicio SMTP\" <*********@gmail.com>";
SMTPClient.Body.szRAM = RAMStringBody;
SMTPClient.UseSSL = TRUE;
Ahora a por HTTPS