I am replaying The Omega Stone after about 15 years, and it has not got any easier. Chicken Itza was an absolute pain but I managed it in the end, but the underground trekking almost drove me up the wall.
Now, however, the Stonehenge section is proving problematical in that I cannot see the letter or the key that Gil was supposed to leave in the vehicle.
I tried going to another part of the world and then returning to Hump in the RV but the information remains hidden.
Any help would be gratefully received.