Obviously, the file interfaces.ppu for carbon is not found. Therefore, it searches for interfaces.pas, which is also not found. So you could check whether they are present, but not found because the path to its place is not checked. A common reason is a 32 bit vs 64 bit problem. The carbon interfaces are 32 bit only, but fpc's default could be 64 bit. Therefore, you should check the settings for the compiler path in the lazarus options. If it is set to fpc, it might help to set it to ppc386. Also check the settings for the cpu target and try, whether changing the cpu target from default to i386 helps.
You can also enable verbose logging with the compiler option "-vt". This will produce an enormous amount of output.
Just don't give up. Although tricky, it can be resolved.