I accidentally duplicated  please delete

1 minute ago, Juninh567 said:

Is it possible to convert ClassiCube's .cw to MCGalaxy's .lvl?

Yes, using MCGalaxy you could create a local server and input it in the folder /extra/import/ 
Then through console you could do /import levelname.cw 

This in turn will import the classic world into a .lvl in the /levels folder in which you can grab the map from 

like umbreoclaw  said, it worked for me lol