In this paper, we study regularity and asymptotic dynamics of a genera
lized complex Ginzburg-Landau (GL) amplitude equation. We show that th
e solutions belong to a Gevrey class of regularity and are real analyt
ic in the spatial variable. We use this to derive an adaptive method b
ased on Galerkin approximation and show that it converges exponentiall
y fast. We also show that the equation has a finite dimensional compac
t global attractor, and has at most two determining nodes. This result
, which depends on regularity, implies that asymptotic behaviour can b
e determined from a small number of observations in physical space.