3. On the desktop, the icons are only displayed in 16 colors

 

To display icons with 256 colors on the desktop you have to run Windows in high- or truecolor mode and either need the Microsoft Plus Pack or you have to make an entry in the registry: Add 'Shell Icon BPP' with the value '16' to 'HKEY_CURRENT_USER/Control Panel/Desktop/WindowsMetrics/'.

It's much easier to do this with the included IconWizard (last icon on the horizontal toolbar).