I don't know if I could post that question here, but I want to ask if is it possible to edit Sunset Valley? I mean editing full Sunset Valley from game? When I want to import SunsetVally.world CAW is saying that it can't be loaded because of compressed file. I was trying to decompress this with Decrapify, but it didn't help. So what should I do then? I'd be glad if somebody will reply me.

The Sunset Valley CAW files are here: https://cawster.wordpress.com/2013/04/04/sunset-valley/.

Okay, thank you so much. Also I found that thread here, and I think it could be helpful. http://modthesims.info/t/469942
This thread is able to be closed

Also, are you aware that most files you download are compressed and must be decompressed with a program like WinZIP or WinRAR? For worlds, open the compressed file and use the program to extract the Sims3Pack file somewhere like your desk top or a file folder. Then, double click on the extracted file to install it into your game via the launcher. I wasn't sure if that was what you were referring to or not. Good luck with your project!