Debug failing NUCLEO-L152RE
Glad that you solve the problem,
Normally should work also with the OpenOCD that is installed with System Workbench. OpenOCD is installed on this path: \Ac6\SystemWorkbench\plugins\fr.ac6.mcu.externaltools.openocd.win32_1.3.0.201507241045\tools\
This seems to be a win32 executable. Nevertheless seems to work in x64 environments.
Unfortunately last time when I have checked I was not able to start OpenOCD that came wit SW from command line because some paths were not corrected set. If the OpenOCD starts from IDE then the correct paths are added.
If you want to further investigate then maybe you can compare Freddie Chopin OpenOCD logs obtained with -d3 option with the default SW OpenOCD logs.