Colorpickerdropdown editors are occasionally misdrawn when the application has a vcl style enabled.
Here is an image of the problem: https://onedrive.live.com/redir?resid=CC082F39C30AB4E8!71011&authkey=!AEDUMC9V0CpiHHo&v=3&ithint=photo%2cpng
To reproduce this, place an advstringgrid, and Enable editing of the grid. and add AEditor := edColorpickerDropdown; to OnGetEditorType. Enable the Luna VCL Styles. Run the program and repeatedly click a grid cell and you will eventually see a glitch similar to the one picture in the link above. This glitch occurs regardless of the grid's styleelements settings.