@jgstew - thanks!
Note: I updated the Validator Tag’s Regex match to narrow down the input field for the IP address range (lines 6/7 below):
ParameterValidatorTag
</MIMEField>
And also tweaked the Metadata Tag’s “Description” field (line 7 below):
<MIMEField>
<Name>ParameterMetadataTag</Name>
<Value><![CDATA[{
"IP_Address": {
"Name": "IPAddress",
"Title": "External IP Address:",
"Description": "Enter the External IP address in the format: xxx.xxx.xxx.xxx where xxx=0-255",
"UIType": "Textbox",
"CustomValidator" : "validateIP"
}
}]]></Value>
</MIMEField>