I'm testing the Framework Version 1.5.2 and the Plugins 1.5.1 on our systems. While everything is fine on Windows Server 2016 and 2019 with PowerShell 5.1, the new moudle versions doesn't work with PowerShell 4 and Windows Server 2012R2. Version 1.4.x is still working fine.
Here are some error messages:
firewall

timesync:


It look like the triggerd check functions for warn/critical doeing something diffrent in the new version. Every of these functions calls Compare-IcingaPluginThresholds. Is it possible that this one doing something wrong? Or one of the Convert-functions you are calling? Maybe a constructor call which is only possible in PowerShell 5.x? I didn't find anything which could create these error messages.