  We address a few subtle issues regarding the interacting D0-D8 system. There
are two existing interpretations for the counter-intuitive non-vanishing
cylinder-diagram R-R potential. We improve them each by properly dealing with
the divergence of potential in the R-R as well as the NS-NS sector, which has
been ignored so far. We further test them by considering the D8 to carry a
flux, electric or magnetic. We find that the improved interpretations continue
to hold. We resolve a subtle issue regarding the regularization of fermionic
zero-modes in the R-R sector when the D8 carries an electric flux so that a
meaningful result for the potential can be calculated. The persistence of
divergence for the potential in either sector in the presence of a flux on the
D8 brane indicates that adding a flux/fluxes on the D8 brane doesn't help to
improve its nature of existence as an independent object, therefore reenforcing
the previous assertion on D8 branes.
