You've missed out some key details that would help people understand what you're trying to do and how to help you.

What software are you using? How are you doing the reactive lighting? Can you reword "I just duplicated my composition, moved it to the top and then pressed add I then drew the were I wanted the lighting all thats done" in a way that makes sense? What does "shorten the top composition" mean? In what way do the pics go weird?

And so on.

My sincere apologizes to Oldscratch and BertL.

Oldscratch I'm using After effects for post work, I am doing the reactive lightning by pressing on the original composition and then copying it and pasting it again, hence duplicating it. I then dragged the duplicated composition to the top and then changed the mode from normal to add.

I then used a paint brush to circle off just were I want the reactive lighting to be applied. It goes weird because the minifig is moving the reactive lighting just stays where I originally made the circle for the reactive lighting so as my character moves my main problem was the reactive lighting circle I made doesn't move with him.

It also goes weird as when I shorten the duplicated composition it overlays on other images from the original composition.

I hope this makes better sense, also here are the images and the video to the file. 

And is there another way of doing this kind of lighting? Can motion tracking be used with this to follow the character and how would it work?

Also here is the video. https://www.youtube.com/watch?v=Cw_I0E4SxOY

Sincerely,
Divine.

You are never going to be able to achieve perfect fake lighting from the torch unless you recreate this scene in 3D space, track a light source to the torch, then composite the rendered light layers over the top.

This is very difficult to achieve.

Your best bet is to track the torch in ae (you will already have a track for the torch)

Add a light and camera to the scene

Colour pick the the colour of the torch for the light

Parent light to the torch

Now duplicate your base layer, make it 3D and turn on accept lights.

for more control, roto the minifig and create a matte for it, then isolate the light.

Honestly it seems like you want perfect 'reactive' lighting as you  call it, but this wont be possible without a lot of hard work.

Rsteenoven,

Thanks for your response, I read through it but am unfamiliar with your terms, are you able to give instructions on how to do what your explaining and where they are it'd be so much easier, and I could make attempt to it.

Telling me in these hard terms makes it very difficult on my part, but of course I do appreciate it.

is it really this hard to do for a simple effect?

I really am confused with some of your terms, parent light to torch?

How do you make a layer 3D?

I really don't know these things so if you could write a brief simple instruction that'd be awesome. As I'd love to do the effect and learn it.

Osomstudios, what do you mean by panted? If you mean painted no you can't I attempted this and it didn't work. I think it may be possible but the way I did it didn't work.

Sincerely,
Divine.

Start by watching some basic tutorials on how to use After effects, Divine.

The terminology I used is basic for the software so you really need to familiarize yourself with the program first.

Cheers,
Rich

No one will do this for you because doing ithe in AE would be harder then resorting the whole scene with a light on the torch.  That is the long and short of it, if reshooting is to hard why would you spend even more time on a digital fix that would be harder and take more time and effort then that?