after spending far too much time with a code 52 which would not let the driver work, I run the following to disable the driver signature enforcement in Windows 8.1.
On an elevated CMD to disable:
bcdedit -set loadoptions DISABLE_INTEGRITY_CHECKS
bcdedit -set TESTSIGNING ON
to reanable:
bcdedit -set loadoptions ENABLE_INTEGRITY_CHECKS
bcdedit -set TESTSIGNING OFF
To check what are the current settings run bcdedit on an elevated cmd
Be aware that although I had installed the drivers when the driver signature enforcement was off, as soon as I enabled it once again the drivers where back to not working with code 52.
Despite many guides which will advice you to follow the GUI approach to achieve a one off startup with the driver signature enforcement, this seems to be a quicker and more permanent solution.
This is certainly not an ideal solution but a good enough workaround.
Update:
Mikroelektronika has now released new drivers which fix the problem. They can be found at this link