It tries to create the exe, but does not find the object-file.
as.exe is not the file you created, but the gnu assembler.
I don't know why it is called or why it is in the temp directory (it should be in MinGW's bin directory).
It looks like you messed up your settings.
I suggest uninstalling C::B and MinGW, removing all remaining MinGW and C::B files and folders and the C::B configuration.
The C::B conf-files are in %APPDATA%\codeblocks.
After that you should install C::B 10.05 with MinGW bundle.
C::B is "just" an IDE that can work with many compilers.
On windows we provide a bundle with the MinGW compiler suite (TDM's gcc in 10.05) for the users convenience.
If you do not install any other compiler you can (of course) not use it.
By the way, I compress my png's with pngnq on linux.
It's not totally lossless, because it creates a 8bit palette png, but the png's are about 40% smaller than yours and the visual difference is nearly unnoticeable.
It uses the
neuquant algorithm and works pretty good.