Please, can someone comment on this?

While running through Keeper FX, there is only one flag available when I start the game (on the map), with a T on it. There is another one, with a O on it, but it's grayed out.

But when I launch the game without Keeper FX, I am able to select the grayed out level and play it (it's some sort of time trial and bonus level where I can get a minion).

Anyone know what is going on?

Why can I not select the level through Keeper FX?

thats the full moon bonus level.
I suppose that the calculations been altered slightly, so that it better reflect when the full moon occurs in your area.

Over here in the uk, it's grayed out in both versions.