What macos version are you running in those Macs?
I am developing and using KLog in Linux (Debian testing) and macOS Mojave
and only testing and sometimes using in Windows 10.
It works in all my systems...
The DB initialization is in the very first moment of KLog... just before
many things are done as most of KLog is based on the DB to work.
I can create for you a debug package of KLog 0.9.6 (no sense to keep
working on 0.9.5), that will show MANY messages in the console so we can,
at least, which function is causing the crash...
Just let me know and I will try to create a .dmg for you to test.
Regarding the changes... between 0.9.4 and 0.9.5...
The main one is the addition of the Statistics that are using a new library
There are also some changes on the DB regarding the satellites.
Are you installing KLog from scratch or updating?
Are you removing the ~/.klog when you go from 0.9.5 to 0.9.4?