FazedReality is the creator of this altered theme which also fixes some bugs of the original one. (I hadn't noticed any of these1). There is a problem: you can't install this normally because it is not signed by Microsoft. So one way to it is by patching Windows. Follow the instructions below.

UXTheme patcher will enable your windows installation to use any theme, not only MS signed ones. Some users had some problems with it (especially on x64 XP). Also after major updates of windows this may have to be run again. If you run the patcher on a previously patched machine it will offer you the choice to reinstall the normal uxtheme.dll file of windows. So this is generally a safe program to use. Anyway use this at your own risk.

Download the Zune Fixed Theme by fazedreality from here . Don't run this for now.

Download the UXTheme patcher from here .

1) Run UXtheme Multi-Patcher v5.0. If you are brave enough press "Patch".

2)  The following dialog appears to inform you of your Windows installation. If everything looks fine, press "OK".

3) A UXTheme Patcher information dialog appears. Don't click OK now, wait a few seconds. 

4) After a few seconds the Windows dialog below appears. Press "Cancel".

5) Another one appears. Confirm this one, press "Yes".

6) Windows now knows you are determined. Press "OK" on the UXTheme Patcher program. A restart dialog appears. Press "OK" to restart your computer.

7) After the reboot run the "Zune_Final_by_fazedreality.exe" you downloaded earlier. Select as an installation dir: C:\Windows\Resources\Themes . Press "Extract". You may be asked if you want to replace some files. Select "Yes to all". 

9) Don't press OK or Apply, but go to the "Appearance" tab. Here you can select among 10 different variations of the original Zune Theme. Have fun :) 

links:

fazedreality's Zune Fixed Theme

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