If you want you can create your own themes for the new installation wizard.
Open the GUI Editor > Open Gallery > Select folder Themes > Right Click on the Themes Folder, and choose "Add Folder" > Type in any name plus the Theme.

For example, "My Blue Theme"
Select the folder you have just created, so that you see in the right pane of the gallery an empty space. Open any project. Drag and drop any Popup or Page into the right pane of the gallery.

To test, just create a new project. In the project Properties screen, click on the "Start" button in the Wizard section. Now  you should see in the drop down list of available themes your new theme.
mybluetheme__1_.png

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