Nope. In fact you're one of the first not to love it.
I advise you to not play any further, because you may start liking it as well, which could easily costs you 2 years of your life.
not be able to do anything else in the game
No chronom maps? No custom maps? You must be playing an illegal version. So why complain about your money?
Lol. Nice observation. The custom maps alone make this game worth the purchase. Plus, if you buy the CW1&2 pack, it's that much more worth your money spent. Not to mention, compare this to the price of one PS3 game. I love my PS3...but, I find I play CW1&2 more often. They're just so deep.
I am fairly new to the rts/tower defense genre and I still beat Tucana. And it was pretty ugly and inefficient compared to the walkthrough video. I watched the video after I beat the level and thought to myself, "wow...I sure hacked my way through this one". So, this level is definitely not impossible. Nor does it diminish how good the game is in its entirety. Persistence pays off.