ToME: the Tales of Maj'Eyal

Ok this definitely qualifies as a dumb question on my part , but I cannot seem to figure out, how to activate the Far east Portal that you find on the 4th level of Reknor (after killing Golbug the destroyer). You do not get an option to enter. Do I have use the far portal instead in the Sher'Tul fortress instead?

Thanks.

After killing Golbug, there must be an orb dropped. Orb of many ways, to be precise. When standing in the portal, just activate the orb.