A2Billing Customization

We have already following component installed on our server Asterisk A2Billing And following features enabled calling card Callback SMS callback & registration I need to have some customization and performance improvement as followings: For calling card application I need followings: 1) We want to print vouchers not PIN on our distributed cards, so whenever new customer wants to register, this voucher should auto generate PIN(Customer) 2) Top up should be possible by pressing * or *33# and then dial voucher number for example: when a registered customer make a call to access number and IVR announce the balance, it will be announced "please enter your destination number or * to top up", if the customer dial *, it should say "please enter your PIN number" 3) SMS registration customization 4) Any new registration and account creation, an SMS need to send to customer to inform about his PIN number For callback application: 1) Faster callback (now there is long delay for callback after receiving miss-call trigger or SMS trigger) 2) Stable callback with high performance 3) SMS Customization(When receive a text start with 11 or r or R, this is a voucher and need to create a PIN or top up a PIN, but any text start with 00 is for callback)