Looks like you'll get this a lot but.....
Your tank simply does not have enough light output (watts) to accomodate an anemone. It looks all shriveled, I am not even sure what that is... I'd seriously consider taking it out of there and taking back to the LFS. If it begins dying, it'll release something very toxic and wipe out your tank leaving you start back to the beginning.
You should have definitely read about anemones and their needs before having bought it. They need good light and be fed well. (ex. krll or some silversides.
My girlfriend has the 12 gallon nanocube dx like yours. 48 watts and all, but no anemones....just assorted coral frags here and there. I attempted getting a long tentacle plate coral to substitute the look of an anemone but failed at that myself. The one I had in a jbj 12, started expanding 3 times it size, and had to sell it to a friend. I then attempted it one more time, with a plate i believed looked tiny, but I let the shell fool me. The plate diameter was that of a small drink coaster, but in my 6 gallon it did the same deal, expanded like I bought something insanely huge, but it's just the way it was...it was trouble....it stung the hell out of my frogspawn frag (nearly killed it) and attacked my galaxia frag which hurt that pretty bad. I have a part that's bleached dead because of it.
Anyway moral of the story, realize first what you are buying by doing your research and talking to a few people before getting yourself in a pickle. Hope everything works out for you and you do the right thing. Keep us updated nanodude.