Was Prime the only original Autobot still around during that time?

 

No. Many others, most likely characters like Wheelie and Hot Rod were muuuuch younger and probably would've laste longer.

 

What ever happened to them?

 

Eventually, they would have died.

 

Died meaning gunned down or old age?

 

Who knows. That's unrecorded "history."

 

Probably both or some might of had their sparks ate by Megatron.

 

Not necessarily. We know some Autobots/Decepticons who survived the great war eventually upgraded to Maximal/Predacon bodies and were still alive and well in the Beast-era. Ravage and Grimlock for example.

 

The members of The Maximals and Predacons that came to Earth were they originally Autobots and Decepticons or new Warriors?

 

No, they were different characters.

 

The ones that downgraded down to Maximals and Predacons were they still around when Primal left Cybertron?

 

Why do you ask such redundant questions?

For the most part.

If you add up the continuities from Headmasters, Masterforce, Victory, Zone, Battlestars, Operation Combination, then it makes sense since Prime revived. Then we can either go with American G2 or the Japanese G2 comics.

Either way works... Somehow...

 

The Maximals and Predacons aren't a downgrade. Technologically they're more advanced than Autobots and Decepticons.

At any rate, yes, some of them are still around when Primal left Cybertron. In fact, Ravage shows up in the Beast Wars cartoon. And Grimlock shows up in the comics having been one of the Axalon crew members in a stasis pod.

 

As far as i remember Megatrons plan was to go to earth and turn the war in the decepticons favour and establish the Predacons as the dominant faction. When he saw the second moon he, and the others, thought it was the wrong planet. after season 1 he picked up this goal again and then after a few encounters with the Vok he decided being part of the ruling faction wasnt enough, he wanted to be a god.

As for Prime im pretty sure the writers have said after the war he went off to explore the universe and was still alive after the great upgrade. Maybe getting a new body extended all their lifespans because ravage didnt seem old by transformer standards.

 

How did Megatron know he was in the past?

 

I think it was his intention. The golden disk contained a recording from the original Megatron telling a successor how to go back and change it all to carry on the work and if possible retroactively win the war for him to place the future decepticons in power.

 

When the second moon blew up. It was then he put two and two together.

Or by "he" do you mean G1 Megatron?

He learned it from the disk.

 

The Maximals said they were on an exploration tour how did they start chasing the Predacons

 

both ships went through a transwarp portal and land on past earth

 

They explain it in the first episode. It's one of the first pieces of dialogue.

And I'm not going to tell you because seriously, all these questions can be answered by just going and watching the show, dude.