OK, I think I got it figured out. Just needed to add some more include files.
Now I got errors like this:Error 81 error : `int CMUI_String::$_19' is not a static member of `class CMUI_String' W:\Amiga\Drives\Development\MUI\PlusPlus\Source\Lib\\mui.cpp 1438 1 PlusPlus
Error 56 error : `ULONG CMUI_Window::$_17' is not a static member of `class CMUI_Window' W:\Amiga\Drives\Development\MUI\PlusPlus\Source\Lib\\mui.cpp 837 1 PlusPlus
Error 61 error : `ULONG CMUI_Window::$_18' is not a static member of `class CMUI_Window' W:\Amiga\Drives\Development\MUI\PlusPlus\Source\Lib\\mui.cpp 842 1 PlusPlus
Error 55 error : abstract declarator `ULONG' used as declaration W:\Amiga\Drives\Development\MUI\PlusPlus\Source\Lib\\mui.cpp 837 1 PlusPlus
Anyone got any clues regarding what's going on here?
Usually when I get those kinds of errors in java, it has something to do with one class being declared static when the class it implements(implemented by?) is not.