How to change base Calendar colour

I really like the standard calendar however I wish to change its colour.

I read another thread which said the gadget info was stored here: C:\Users\Stu\AppData\Local\Microsoft\Windows Sidebar

and could be edited (like html for colours etc). However only my custom clock gadget was there - I didn't see any info on the Windows gadgets.

Anyone know a way to change the background colour of this calendar gadget?

Edit: Can someone mark this thread as solved please :)

Hey etrifonoves - cheers. I found the files you were talking about. Unfortunately when I finished editing them it said I didn't have permission to save over them. Nor could I save as, then delete the original and rename the new files (again, it said I did not have permission).

I am the only user of this computer, shouldn't my login have Admin rights? Or is this not a user security issue and theres another way around this? Any help appreciated.

Gah I'm so newb.. that deviantArt pack was just what I wanted, but again I can't copy over the old gadget files (no permission). How do I ensure my single user has admin rights? I've tried playing with the permissions on the Gadgets/Sidebar folders, but it denies the changes.

Edit: Ok I'm inching my way closer..

I followed this link to enable 'take ownership' in the context menu. I did that, and managed to replace the gadget files. However when I launch the gadget again, the old files are still being used somehow?

Edit2: Ok I still don't know why the original calendar mod I did didn't work, I do have a better solution though - downloading this awesome gadget set. Includes the stock calender modified to black with opacity settings - perfect!