Hi, Giuseppe-

You are free to set things however you see best fit---tailor the GUI to your viewing preferences! And you can always adjust it later, for different data or a different study, say.

To get the former behavior, you can put:

AFNI_AUTORANGE_PERC = 100

in your ~/.afnirc.

Indeed, that first message was from the AFNI History log:
[afni.nimh.nih.gov]
and so when it was first introduced, it was set to zero. But now the default is 95.

Note that we are also big proponents of *showing* your beta weight (=Coeffient) values in the overlay, and thresholding using the stats---reasons are discussed here:
[pubmed.ncbi.nlm.nih.gov]
... and here, in this AFNI Academy lecture, discussing the mechanics of it in the GUI:
[www.youtube.com]
... and in that latter video, we even discuss "translucent" thresholding with the alpha+boxed functionality in the GUI. It is worth checking out, for displaying more of your hard-earned data analysis results!

--pt