thanks for the post.
I have tried the SMTP example in installation with my Google account and it was also rejected by the Gmail SMTP server. Thanks for pointing out this issue - I have already handed it over to our developers.
In the meantime you can use a workaround with some command line utility as you proposed. Have a look at function block called EPC or better use example 0304-02 MP3 Playback.
There is also example on E-mail notifications using Python script - see example 0304-01 E-mail Notifications.