Colours for display items are changed using the Colours property page on the Tile Display Parameters dialog window.
If a single colour is appropriate, for example when the colour for the Tile Background or the 3D Fill colour require adjustment, then the Basic Colors section on the Color dialog window is used to pick and individual colours. Whenever more than one colour is used to differentiate between display-items, such as overlaid spectra or multiple synthetic components, then the set of colours are defined by the palette of Custom Colors on the Color dialog window shown in Figure 1.
To change a set of colours for Spectra, say, the Spectra button on the Colours property page is used to invoke the Color dialog window. Initially the Color dialog window displays two tables of colours, the Basic Colors and the Custom Colors. To modify the Custom Colors table, press the button on the Color dialog window labeled Define Custom Colors >>. The auxiliary colour parameters section will appear to the right of the Basic Color/Custom Color section and using the colour defined via these additional controls, displayed in the Color|Solid colour pad, the individual colours in the Custom Color table are updated. These Custom Colors entries are updated by first selecting the required entry in the Custom Color table, making the adjustment to the colour using the parameters on the auxiliary parameter section and pressing the Add to Custom Colors button. The Add to Custom Colors button causes the selected entry in the Custom Color table to update. Once the table of Custom Colors has been prepared, the OK button on the Color dialog window is pressed followed by pressing the Apply or OK button on the Tile Display Parameter dialog window. It is not until the Apply or OK button is pressed on the Tile Display Parameter dialog window that the spectra in the Active Tile are displayed using the new palette of colours.
Tip: If you wish to set all the Custom Colors to the same value, select the top left entry in the Custom Colors table, adjust the colour in the Color|Solid colour pad and repeatedly press the Add to Custom Colors button. The table of Custom Color will fill with the new colour from top-to-bottom, left-to-right.

Figure 1