I have been on a Chic kick lately thanks to Sergio and Shawn. Now, either I am seeing things, or even Nile has the couple of the chord names in "Everybody Dance" wrong. It's clear that the first chord in the song is Cm7. However, the second chord looks like an F major chord played on the 4th fret with the addition of a 9th interval on the bass string. Everyone seems to assume that the bass note is the root note. However, if one examines the notes in the chord, one discovers that they are Ab, C, Eb, and Bb, which would make this chord Abadd9, not Bb11. The notes in Bb11 are Bb, D, F, Ab, and Eb (Bb11 is Bb7 plus the note Eb). Nile does not appear to fret or play the high E string, but that omission does not change the chord. I believe that the third chord is the same shape moved up two frets, which would make the chord Bbadd9.
In the drawings shown below, the number in the circle represents the finger that is used to fret the chord.
The song is in the key of Cm/Eb. The notes in key of Cm/Eb are Eb, F, G, Ab, Bb, C, and D.