As integration was developed based on older version, I suggest you to test if it works with 3CX Phone System version 15.5.
Also, you could ask other partners. Might be they have customers using this version.
I would like to know what BackgroundHALShouldPause does, and how to use it. While it's listed in the HAL Primitives report, it is not used in source code and it doesn't appear in the LMS HAL...
