Daniel,

When deciding on centering strategy, do you believe that those groups are intrinsically different in terms of movement? In addition, the following line

-qVarCenters '(0.0450,0.0607,0.0575,0.0492)' \

is not valid. If you want to center each group separately, you have to manually perform the centering yourself before putting the quantitative variable values in the data table.

> if I look at the results of the MVM on the brick showing only the effect F of "Group" variable
> I don't get exactly the same results as the ANOVA without the covariate

They should be different because including an extra explanatory variable in the model would change the dynamics of the model. Check out the Movement effect in the output and see if it's reasonable to include the covariate.

> is it the same to put the quantitative variable Movement inside glfcode and gltcode or not?

It's not clear to me why you need the GLF specification. If you are interested in group comparisons, you should not include the "Movement :" in the GLT specifications. Do that only if you want to compare those groups about their Movement effect (slope).

Gang