1) Why is the SMS channel greyed out but the channel is enabled and my balance is topped up?

If you have the SMS channel enabled with funds available and the option to send an SMS is greyed out, do check that you have the leads mobile phone number listed in the mobile field on their lead profile page. Once added the SMS option will become available.

2) How do I add a subject line when using the Email Template?

To ensure that you have a subject line included when using a template add the subject line in the Subject line, then press Template.