Somehow after the Hive of the Mantids episode the Primagen key 1 disappeared from the hub. I know it was there because this is the first one I got after getting the jump capability and it was indeed in place when I put the Primagen keys 2, 3 and 4 in place. I tried going back to Adia Port Village directly to get it but it was no longer there even though the jump pad was at its place. A search on GoG forum and the net brought no solution. Finally I decided to go into the hub portal for Adia port and go through the whole episode without any fights (safe for when I got close to a save portal) nor children saving obviously, and when I reached the village the key add reappeared and I was able to get it for a second time. Got back to the hub and put it in place once more. Hopefully it will remain there after episode 6 .....