Here's my attempt at a first Kix script:

$DefaultGateway = ReadValue("HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\El90x1\Parameters\Tcpip", "DefaultGateway")
$SubnetMask = ReadValue("HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\El90x1\Parameters\Tcpip", "SubnetMask")
If @ERROR = 0
If $DefaultGateway equals 169.112.1.1 AND $SubnetMask equals 255.255.255.0
? "Default Gateway: $DefaultGateway"
? "SubnetMask: $SubnetMask"
EndIf
Endif

Question:
How do I correctly replace what's in bold? I want to check for REG_MULTI_SZ (multi-string) values. TIA