Check whether certificate has been imported inside cacerts keystore successfully, use keytool -list -keystore <Path to cacerts> | more

In server settings(Workbench), you should provide the hostname as there in your certificate(i.e. hostname + domain).

Point to be noted : Ensure that you connect to HTTPS by using the name that is specified in the certificate. This name is typically the fully qualified host name.

Make sure you have completed this step : http://help.adobe.com/en_US/livecycle/10.0/InstallWorkbench/WS624e3cba99b79e126ac9118f12f365f04a9-7ff3.htmlThanks,Wasil

Check this out : http://help.adobe.com/en_US/livecycle/10.0/ProgramLC/WS624e3cba99b79e12e69a9941333732bac8-7112.htmlThanks,Wasil

I am not sure how to do this but if  this field has any dependent field using which it is calculeted, then the dependent field could be used to set the value and subsequently show the pop up message.

The validate event might cause the script to run multiple times here. You can use any other event to notify the user for the threshold value. Please have a look at the flow.Thanks