Ista 4.27.22 issue

[properdouble]

Hi Guys
I have installed latest ISTA and it work ok , connect to car , scan for errors however soon as i click on service functions it stop responding. Iam using ENET cable , car is 2016 F25 LCI B47 engine. i need save up for proper power supply and get an ICOM Next from china cause as a start i would like to update sat nav and switch off thios annoying Start-Stop function. 
So the question is would low battery below 12.55V (i got message pop up on ISTA screen) would cause service functions not operating and ISTA freezing. I mean i have spent last 3 days from friday after work up until now recovering and installing ISTA over , the only last working version i had was 4.18 i think . I could preety much do any service function there is without worrying for voltage.
I would appreciate any help or suggestions.
Regards