If you are using Graphical Installer for Inno Setup together with InnoTools Downloader (free third party plug-in to download files during installation) you may noticed the ITD plug-in has unpleasant bug.

E.g. like in this question: http://stackoverflow.com/questions/17813754/changing-layout-options-of-inno-setup-downloader-tool-with-graphical-installer

ITD plug-in creates simple form which contains download progress bar and few labels with download information. This form is not visible in regular installers (because they are usually grey). The problem is when you try to use ITD with background skin - the form becomes visible as grey rectangle and the installer does not look cool:
ITD bug

The only way is to modify the ITD because it was not designed to work with Graphical Installer. We already modified sources (it is written in Delphi/Pascal) of this plug-in and updated it to work perfectly.

It requires only two extra lines of code to initialize the 'new' ITD:

// Initialize ITD

And the resulting installer again looks cool:

Use updated itdownload.dll and it_download.iss in your script - see example for more information.

You can download whole example here (1.11 MB).

Update 2016-03-30:

- Fixed download link