We apply group cohomological methods to calculate the cohomology of $\Kn_*\BP$ as a $\Kn_*\Kn$-comodule, recovering recent results of Hovey and Sadofsky. As applications we determine the Chromatic Spectral Sequence for $\BP$ based on Johnson and Wilson's $\En$, showing the relationship to some generalizations of the classical Hattori-Stong Theorem and determine the change of Hopf algebroid spectral sequence associated with the natural map $\BP\lra\En$, extending calculations of Clarke for the Todd orientation $\MU\lra\KU$.
Homology, Homotopy and Applications, Vol. 2, 2000, No. 3, pp 29-40