Carl,

This is not a recommended method by ServiceNow but i am giving you the script only to over come the issue right now. Would strongly suggest workarounds.

Script:

Make sure you are adding the right field names and use alert conditions if you want to debug.

var sub = g_form.getDisplayValue('subcategory');

var sys;

var ci = new GlideRecord('cmdb_ci');

ci.addQuery('name',sub);

ci.query();

while(ci.next())

{

sys = ci.sys_id;

}

g_form.setValue('cmdb_ci',sys);

*This will work only when you have a condiguration item with the same display name as of subcategory.

Let me know how it goes and mark Helpful or Answered and make help improve community experience.

~Raghu.