Adding a large port range to NTA Multi-port application seems to hang

I am trying to add a large port range to a multi-port application in NTA.  For whatever reason it seems to hang/not actually do anything when I hit Add (or Update Application) button in the pop out window.  If I add single port or a smaller port range (eg: 2100-2200), it works fine.  Anyone else experience this behavior or offer any advice?  NPM 12.0.1 with NTA Version 4.2.1.  Have tried in different browsers, Chrome, IE and Firefox, both from a client machine and via the Orion server.  I should add that if I click on the Cancel button, nothing happens either.  I basically have to close the browser tab to get out of that screen.