These *.dat files are actually tab-delimited ASCII text and can be imported 
into Excel or read directly into Matlab.  I was able to read one into Excel
using Office 2008 for Mac.  Basically, what you collected are time-series
of spectral Lu(lambda,0.6) and Ed(lambda,0+).  If you propogate Lu to the
surface (Lu(0-)) and cross the air-sea interface (by multiplying by 0.543), 
you can will be calculating Lw:

Lw = 0.543 * Lu(0-)

Then calculate Rrs as Lw / Ed(0+).  There are various ways to estimate
KLu to help propogate Lu(z) to Lu(0-) -- calculate it using the "profile"
data collected by Group 1, model it using Chl (a la Morel 2007) or a and bb
(a la Kirk 1984), or find som published values of turbid Kd(lambda).  
Remember Kd is spectrally dependent in this kind of water.  Don't worry too 
much about getting perfect KLu -- the point is to acknowledge that the TSRB 
collects subsurface data and doesn't provide independent information to 
estimate KLu or Lw.  Call with questions, I'm around to chat.

Only use the files titled "buoy*" ... not the KA or OO.