You can test with http://web-shield-test.avast.com/ and http://test-url-blocker.avast.com/.

Once you turn off shields and start them again, you’ll get pop up again.

Regarding your malware samples, don’t post them here. However, are you sure they’re not from the same domain? A prime example would be AMTSO. Since they’re coming from same domain after detection of of the first file, you wouldn’t get the popups… same for EICAR files.