Help with relevance needed

I have created a property in BigFix that will display the status of “McAfee Solidcore”. If “McAfee Solidcore” is installed, the property will read the registry and based on its settings will display what mode “Solidcore” is in… update, observe, disabled, etc. That part of the relevance works fine. The part that does not work, is if “McAfee Solidcore” is not installed on the system. Instead of reporting “N/A” in BigFix on systems where “McAfee Solidcore” is not installed, it displays . When I test the relevance on a system without “Solidcore” this is what I get:

Q: if (value “RTEModeOnReboot” of keys “HKLM\SYSTEM\CurrentControlSet\Services\swin\Parameters” of registry as string) contains “0” then “Disabled” else if (value “RTEModeOnReboot” of keys “HKLM\SYSTEM\CurrentControlSet\Services\swin\Parameters” of registry as string) contains “1” then “Enabled” else if (value “RTEModeOnReboot” of keys “HKLM\SYSTEM\CurrentControlSet\Services\swin\Parameters” of registry as string) contains “2” then “Update” else if (value “RTEModeOnReboot” of keys “HKLM\SYSTEM\CurrentControlSet\Services\swin\Parameters” of registry as string) contains “3” then “Observe” else "N/A"
E: Singular expression refers to nonexistent object.

Thanks in advance

I tried to do something similar. check this out