Some MOD widget is done by UltraLinx. It is not official support Nexus One, so you need to extract the file and manual ADB push it or root explorer copy it with correct permission.
Minimal Matte Grey/Modded Black Apps - xda-developers
** Only extract Modded_Black_Apps.zip and ADB push in or using Root Explorer copy in and set permission to rw-r--r--
*** The Notification Bar is not support in Nexus One, don't flash it, it was design for Desire.