Thank you for clarify the serial and other things.
I do understand that you always power the ESP8266 from another device on the USB, is that correct?
Myself do have some bad experiance with power an ESP8266 from another device on USB.
Solo programming the unit seems fine until the WIFI radio goes on, and current does go up (a lot at startup).
At this moment my best bet would be the power, so see if you can get another power source, or 2 AA Alkaline bat. to run the ESP8266 as test.
Let us know if you get any better results.
I have separated power supply for the 8266, but the result is the same.
So I tried another approach and i connected to the pin 10 and 11 of the arduino pro mini to intercept serial traffic, and I discovered that the 8266 correctly receive and transmit serial commands and response. It looks is the Arduino board that has the issue.
Could it be due to Library errors?
I Included a shot of the traffic of the 8266 intercepted in the first image.
The second image is the serial Printout of the arduino.
After hours of different tests, the only way to make the device talk with ArduinoProMini ws to reflash ESP8266 to a downgraded firmware 0.9.2.2
This will lock the communication at 9600baud ad then it will work fine.