Sorry I know this is old
It seems the snap is sitting at 0,0 for me, the preview shows it more near the centre of the screen
can't find the line in the layout.nut that sets the coords for the snap, can anyone help me?
Edit,
I added this above the set_snap_dimensions function:
snap_shadow.x = 240;
snap_shadow.y = 80;
snap_shadow.width = 400;
snap_shadow.height = 300;
snap.x = snap_shadow.x - 10;
snap.y = snap_shadow.y - 10;
snap.width = snap_shadow.width;
snap.height = snap_shadow.height;