Well, this is one of the first times we have ever physically seen all of the Thirteen and it was well worth the wait. However, the one question that remained bouncing around my head all through the episode was which one was which. I replayed the episode several time and thanks to the stills on tfwiki i've had a lot of help figuring out which on was which.
Here's the picture for reference (credit goes to tfwiki.net for these):







Here's what i have so far:

Prima-This one was pretty obvious. He's the one weilding the saber and the in the center of the second group shot.
Megatronus (The Fallen)- This one was a bit more difficult to figure out.
I think he's the constantly pictured with a glow around his eyes and aura around his body. You can find him directly below Prima in the third shot, all the way to the right in the second, and towards the left in the shot of the Well of All Sparks.
Alpha Trion- I'm still not quite sure which one Alpha Trion is. He could be the one directly on Prima's left side (the one to the right for us reading). He could also be seen in the third shot right below Prima's hand and in front of Megatronus. EDIT (thanks to shadow2879): He could also be seen in the first pic. He could be the one in the top center with a visible full cloak.
Solus Prime- This feminine bot was another pretty easy one to find. She's the one all the way to the right in the third shot weilding what appears to be the Magnus Hammer and in the first shot the one immediately below The Fallen. EDIT (thanks to shadow2879): It may appear in the first shot she could also be the one in the top center next to Alpha Trion.
Liege Maximo- This was also easy to find. He's the one depicted with the horns in every picture. Behind Prima in the third shot, off to the far right in the second shot, and to the left (right for the readers) of Prima in the first one.
The Mini-con- I think this one is the one depicted with the blue force field around him in all three shots. He stands out like a sore thumb so i don't think I need to explain where he is.
The one with a beast mode- This one was also a bit tricky. I could only find this one in one of the shots. He the one directly to the right side of the mini-con. I came to this because in that shot he seemed to be on all fours.
Vector Prime- Your guess is as good as mine. I have no clue.

So thats it. Who do you think is who based on the above images?

 

Top pic... I can tell you for fact that you are right on the mini-con being the one with the force field around him but (top pic) look at the two center top. Alpha Trion is the one with the full back cape and Solos Prime (the Female is on his right (our left) she has the lower front split-like dress on.

 

On the second image:

Prima: The center one

Vector Prime: The one on Prima's left. He has the same glowy circular thing on his chest Cybertron Vector Prime did.

Alpha Trion: The one on Prima's right. Really long beard, a bunch of robes and stuff. I'm 80% sure it's him.

Megatronus Prime: The one in the distance behind Vector Prime. He has the same helmet design Megatron has.

Mini-con: The one constantly in the glowing orb

Nexus Prime: The one with the visor near Mini-con

The rest, I have no idea. Liege Maximo could be the one with horns near Megatronus Prime. Solus Prime is obviously the only female looking one with the hammer in the other image.

 

You do make a really good point regarding Alpha Trion and Solus. I'll make an edit for that one.

I think you just proved me wrong about Vector Prime and Alpha Trion. I do realise the helmet design for Megatronus but the only thing he seems to be missing is the firey glow he supposedely had.

 

I was just trying to identify each one of them earlier. I got Prima, Liege Maximo and Vector Prime, along with the Mini-con, along with the Beast Guy.

 

Thought I'd try to paste together the scene with them for a bigger image. Hopefully this will help in looking at and identifying them.



(been a long time since I posted anything on here, but I've been getting excited about Prime).

 

My interpretation of it. All the confirmed members are on here. Epic Cloak Dude or the guy next to him may be Alpha Trion. I am unsure.

 

I think Vector Prime is the one with the glowing orb in his chest _____________^

Edit: Never mind. Bountyan beat me to it.  

 

I am not as familiar with the Original Thirteen as most TF fans are. But seeing them in flashbacks was good. Maybe they'll use this as a follow-up for The Fallen

 

I think the dude with the wings in both pictures is the member with a beast mode, most likely an epic looking bird, maybe even a griffin or Pegasus?

 

Epic Cloak Dude? That name should be cannon  

 

Primus wasn't very creative when he named that one. XD

Also, they did show all thirteen in the episode, just not all at one time. Here:



Also, none of them are on fire. Megatronus must not have his flames at all in this continuity, or he adopted them after his betrayal.

 

Guess 2 are

Sentinel

and

Vector

 

I think they are the same guy, that's why I labelled them both 2.They both have the visor, and some other common elements (such as the sweeping fins off the shoulders, and the rounded chest). I personally believe 2 to be Nexus Prime.

Also, Sentinel wasn't one of the first thirteen, in any incarnation. The first thirteen are also not all Primes. Only seven of them bore the title of Prime, and those seven traveled to the movie universe and died there, thus they were exiled from the movie continuity.

 

Isn't he kind of big to be a minicon? I'm thinking Cyber-Ninja - The effect is similar to the Processor over Matter meditation technique TFA showed us.

 

Well one of the original 13 is a mini-con, and he's the smallest out of all them. And maybe his glowing orb has to do with some power up function for other transformers.

 

There's no #13, which would be Megatronus (chaotic number of bad luck, makes sense as the Guardian of Entropy).

 

I think the "shield" is extra defense for him, so he has the same level of defense as the others, as he has less armor on his body and needs a form of compensation.

 

I did label one of them 13, and he is the one wearing the cloak. He and Solus (12) are not in the top picture from my observation, so I labelled them with the remaining numbers. The labeling of 13 has nothing to do with who I think the character is, just he has no corresponding image in the top one. Personally, I think #8 may be Megatronus, as the head resembles Megatron. I am unsure.

 

I feel that the #1 is what you labeled #13.