Hi BriKS
Thank's about the reflow oven 
, at the moment its just a big mess but it does the job 
.
About the Low power version im still in development with this board but the specs will look like this:
ATmega1284p chip at 8 Mhz 128Kb of flash,16kb ram, and 4 kb eeprom
everything else is the same except that in order to save power you can turn off the micro SD card, ADS1115 chip (via Transistor), wifi module and put the main processor to deep sleep.
In order to wake it up from deep sleep you can use pin D6 interrupt or the internal RTC.
You should also be possible to run it of 2.5 to 5V but im still testing all that.
The PCB is a 4 layer PCB that i designed but at the moment i let Eurocircuit make the PCB, Assembly i do my self.
Best Regardes Simon