Please change into "rtcSrcUtils" at 422 row to this:
SystemParametersInfo(SPI_SETDESKWALLPAPER, 0, PChar(Result), SPIF_SENDCHANGE); // SPIF_UPDATEINIFILE + SPIF_SENDWININICHANGE);
PostMessage(GetDesktopWindow, WM_SETTINGCHANGE, 0,0);
This is more fast.
Thank you