Whilst it is possible to send emails from and save emails into Prospect once they are in it they are static and can't be interacted with as you would with an email in another mail client.
At the minute if you want to forward the email you have to copy it into a new email and send that. This would enable users to forward the email thread.
Likewise it would be useful to resend an email that has been sent before. If someone asks for a copy of an email we sent we are not able to provide it.