Please Help to downgrade TCP connected Gateway

I have some TCP connected bulbs and a gateway with the last firmware, of course , the gateway does not works with ST after TCP down the server.

Local request with the gateway its not possible because ST does not support auto sign certificate, the last TCP gateway firmware use ssl .

I bought another gateway and its with original firmware v2 and it does not use SSL , Then I have mod the old SmartApp and Deivice and now my TCP bulbs are alive again.

I have blocked the insternet access of the gateway by mac address to avoid firmware updates.

The response its like 1 second delay, but its ok for me

Everything works like original device

Someone could help me to downgrade the firmware in my first gateway?

There are some instructions in net but I have problems with the python server with certificate,

If some have downgrade the firmware could help me to downgrade my gateway.

Thanks