Edit 1:
Managed to advance the Reptoids. There were some misleading dialog options. I had to select "I can see no other way" which in other conversations is always a dead end or the same as "Log off". I still think this game is rather buggy. The timeline showed that they had begun expanding to other star systems 200 years before inventing a spaceship. I think it was supposes to be a planetary expansion instead of stellar.
Looking through the Entomon dialog there are references to a virus in the food supply. I then have to choose which group to give the vaccine to, Ancient or Mutant. This might determine whether they can survive in space but the event never comes up.
Edit 2: More evidence that the Entomon timeline is broken. When they invent Artificial Intelligence they immediately become extinct. However I found references to a Computer Virus event and dialog to explain the problem. I've also encountered a few events that do appear yet I still get the basic dialog making me think the specific dialog wasn't assigned.
Edit 3: Okay. The Entomon can be advanced. However, I think the conditions may have been too restrictive. I had removed the Gene Splicing Serum before exploring the events after it. It seems the changes to the timeline only occur if I had learned that the Entomon need the mutation first. So having already removed the serum I couldn't trigger the changes.
Edit 4: Advanced all 4 races. Got the ship module from each. Discovered weapons 3, 4, and 5. Still missing weapon 2. It looks like there's a second path for the Reptoids that I haven't found a way to trigger. Some random events have yet to come up and I haven't found solutions for Earthquake or Meteor when they do.
I spent all yesterday trying to balance the races and encountered several problems with this part.
1) If a race is weak or extinct in year 9900, and I remove their teraformer, then place it back in the same year that race becomes the dominant power. Only the race that I interacted with most recently will successfully expand. The others just give up.
2) Removing the teraformer of one race early in the timeline causes the teraformers of other races to either move from where they had been placed or disappear entirely.
3) I can use the ship to defend planets when they are invaded but If I defend one, then defend another in the same year, the first one will be invaded as if I hadn't defended it. Only the planet that I defended most recently in that year will have any effect.
4) Each race has dialog where I should be able to tell them which planet I want them to teraform but I haven't found a way to access this in the game.