3.1i Design Manager includes a new preferences setting (File->Preferences) that allows the user to display a Xilinx Watermark in the background of their Design Manager main window. This setting is is disabled by default on most systems. When enabled, this setting may cause display issues with respect to certain systems.
ソリューション
Display issues that have been reported with regards to above relate to window repainting and awkward color pallete usage. Since this feature had not been tested with the different hardware configuration that are present on certain user's systems, it was disabled by default.