zigbee meshnetics

I buy several Zigbit900 from meshnetics but it seems there is no firmware in its ATmega1281 micro,(only there is a booloader in it) ,I want to work with serialnet (AT command set)

Is there any hex file available for this?or I have to buy thier development kits about 1200S!

Is there anyone familar with meshnetics module?

meshnetics support is too weak,they does not response to questions and I am disappointed for using thier products.