E2N7 is not activated in the world yet.

Oh, so that's how the greyed out rooms work! I thought the greyed out rooms were only "locked" for selection as a spawn point for new players; I thought i would still be able to colonize them by sending creeps there. Thanks for the info.

Oops, typo in my comment and no way to edit:

My creep was even standing on the top-exit in E2N6 and trying to move upwards, but it did not move into E2N7.

I'm seeing bugs like this as well, though i'm not sure a player has previously lived in the room i'm trying to enter. Tried to move from E2N6 to E2N7, and it reports -2 path not found. My creep was even standing on the top-exit in E2N6 and trying to move upwards, but it did not move into E2N6. Navigating to some other rooms seems to work ok.

Do the devs have any tips about how to reduce cpu usage?

Does the size of our js files affect cpu usage very much? (like, are they parsed every tick?) If this is so, would "minifying" our source files reduce CPU usage?

Any other hints or tips about CPU usage?