Saving Mom's work on Ancestry.com

[ScooterCat]

First thing I would do is:
From ancestry.com website, click on "Tree Pages" next to the name of the tree, then select "Tree Settings"
Click on "Export Tree"
Wait till it generates the GEDCOM, then click on "Download your GEDCOM file"
Save multiple copies in multiple places so that you won't lose it if, for example, your computer dies

Is her tree on ancestry.com synchronized with Family Tree Maker?

[D.Clade]

My mother passed away earlier this month. She left us years of work on Ancestry.com and nobody messed with it. We want to preserve her work as is, a master copy of her work.
Using Family Tree Maker deluxe and logging into her account, what do I have to be careful about? My understanding is that doing it wrong could change settings and allow people to mess with mom’s work.
Just want to be extra careful and trust the advice on this forum.
Deep Clade results are due Monday or sooner I hope. Thanks, Joe