dc42:
Those look like linker errors, meaning that your program has compiled OK but the object code library file for the LiquidCrystal library was not found. Either locate the object code library and add it to the linker input list in your AVR Studio project, or add the LiquidCrystal.cpp file to the list of source files in your project.
I meant to say something like that but was incapable of expressing it in an accurate way like you did.