Appointments not been registered, plugin not working

I am very disappointed that the plugin is not working and that I am not getting proper support, whilist paying for this.

I have installed the plugin, and when making an appointment through front end, the transaction (appointment) is not being registered, not emails been sent, etc.

In a few words the plugin doesn't work. I really need to get it functioning. Hopefully you guys can help

Thanks
Fernando.