WPMU Dev Dashboard not visible

I can't see the WPMU dashboard. I've followed the instructions about adding a user id to the wp-config.... define('WPMUDEV_LIMIT_TO_USER', '1, 12');

When I added user #2 as above, I just get white screens like php error. when I change the file back to just
define('WPMUDEV_LIMIT_TO_USER', '1');
define('WPMUDEV_LIMIT_TO_USER', '2');

the system works but I still don't see the plugin. I'm user #2.

We're testing multiple multi-site installs before we go live. This is the first install in which it's not visible to me. Do I maybe not have this site registered with my account for something? I don't see it in the dropdown of multisites (I see lesliegm, gardnertm, test1, etc. but not test2)