The Corrupted Crags is a location in Cyberspace, accessible through the cybergate in Cybergate City after beating the 7th gym.
The NPC at the starting point states that the Corrupted Crags used to be the first virtual simulation of reality, but got corrupted by viruses until it became a glitchy realm of disorder and conflict. She also states that the Pokemon here are more dangerous than the ones in the Data Fields.
The second NPC, located towards the bottom right corner of the map, uses the sprite of a berry tree, and directs the player toward the cavern leading to the Forgotten Depths.
Full Restore: Inside Glitch (note: can only be approached from the right).
Trojorsite: Southwest corner.
Malwormite
Hyper Potion x4: In the triangle of items in the Forgotten Depths, top corner, and along the west wall, both north and south of Nice :). Forgotten Depths, southwest corner.
Max Revive x3: In the triangle of items in the Forgotten Depths, left and right corners, as well as by the entrance (you have to walk by the triangle to reach it).