  We use the Bond Fluctuation Model (BFM) to study the pore-blockade times of a
translocating polymer of length $N$ in two dimensions, in the absence of
external forces on the polymer (i.e., unbiased translocation) and hydrodynamic
interactions (i.e., the polymer is a Rouse polymer), through a narrow pore.
Earlier studies using the BFM concluded that the pore-blockade time scales with
polymer length as $\tau_d \sim N^\beta$, with $\beta=1+2\nu$, whereas some
recent studies with different polymer models produce results consistent with
$\beta=2+\nu$, originally predicted by us. Here $\nu$ is the Flory exponent of
the polymer; $\nu=0.75$ in 2D. In this paper we show that for the BFM if the
simulations are extended to longer polymers, the purported scaling $\tau_d \sim
N^{1+2\nu}$ ceases to hold. We characterize the finite-size effects, and study
the mobility of individual monomers in the BFM. In particular, we find that in
the BFM, in the vicinity of the pore the individual monomeric mobilities are
heavily suppressed in the direction perpendicular to the membrane. After a
modification of the BFM which counters this suppression (but possibly
introduces other artifacts in the dynamics), the apparent exponent $\beta$
increases significantly. Our conclusion is that BFM simulations do not rule out
our theoretical prediction for unbiased translocation, namely $\beta=2+\nu$.
