you downloaded stark's custom crosshairs right?
if go to C:\Program Files (x86)\Steam\steamapps\common\Team Fortress 2\tf\custom\crosshairs/scripts
open tf_weapon_sniperrifle.txt and replace
"crosshair"
{
"file" "vgui/replay/thumbnails/cross"
"x" ""
"y" "0"
"width" "64"
"height" "64"
}
with
"crosshair"
{
"file" "vgui/replay/thumbnails/seeker"
"x" "0"
"y" "0"
"width" "64"
"height" "64"
}