I am using Xfce 4.10 under Xubuntu 12.10. Guake terminal used to be transparent under Xubuntu 12.4 LTS. Now I upgraded to 12.10, and Guake is not transparent anymore (although it is set under preferences accordingly).
Anyone else having this problem? How can I make Guake transparent again?
First of all you need to check enable display compising on Setting Manager > Window Manager Tweaks > Compositor. It enable transparency in all Windows.
But if it can't help you, you can open guake preferences file probably under /usr/share/guake/prefs.glade and look for a lines containing <widget class="GtkHScale" id="background_transparency"> and a child of it that is <property name="draw_value">False</property> and make the False to True like what I do.
at last it works for me...