Have fun !
Hmm..when I open this in 2.8 I don't see any connection between the mesh and the rig? So yes, there is a model and there is a rig in the blend but they are not connected or "skinned" at all.
in object mode grab the mesh ,hold "Shift" then select the armature . press "control p -with automatic weights" than parent the eyes to the headbone "keep offset". now it should work.
You can also model your own spider to use this rig.