We had a look at the submited project but we cannot reproduce the problem. I suspect that the icon is still the cuplable item and it must be that when you build your project the broken icon is being reused instead of a new one being compiled (which reminds me to propose a fix to the Carbide.c++ team).
Please fix your icon and to test it make sure to delete the existing *.mif file from the file system.
To do so automaticaly, add the following lines to the *.mk file that generates your icon (mind the TAB character, it is mandatory to start the command row with it):
@echo .:. Deleting target icon file
del /q /f $(ICONTARGETFILENAME)