Not gonna lie. I'm not sure what's causing your problem. It's supposed to be a lamp so I'm assuming you
vertex painted it correctly? The mesh is horribly messy. It looks like you used the decimate modifier on it. Did you? Decimate is death to topology. It's really only good for the low LODs; the low LODs are only displayed when you're far away from the object so it doesn't matter if the mesh looks terrible. You won't see it. But LOD 0? That one needs to have a good mesh as it will be seen close up.
You've got disconnected vertices all over the place. Put your mesh in vertex select mode and go through and select and move some vertices. You'll see they are not connected. When you have unconnected vertices sometimes you'll see a sharp line. I don't even know how you would go about fixing this. Aside from the beads, there isn't one single place on this mesh that doesn't need help.
The package has five object definitions, as well. It should have just one.
Do you have a high poly mesh that isn't a total mess? If so, you can dissolve edges (shift + alt select edge rings, X > dissolve edges) and reduce the polycount that way while preserving the topology.
If not...honestly? Start over. Remake the whole mesh.
Hide your existing mesh. Select and press H (Alt + H to unhide).
Shift + C to put the cursor in the center of the screen. This is so the new mesh will appear in the center of your scene.
For the horizontal rings, press T to open the side panel and add a torus (shift + A, mesh > torus). You can edit how many rings the torus has and how thick it is (ignore the top right of this screenshot). Press T to close the panel again.
Mark a seam around the inside perimeter and...one at one end. I don't know how to describe that, sorry. U to unwrap it. Move the island off the map somewhere.
Object mode. Numpad 1 to enter front view. Select the torus, shift + D, then enter. This will duplicate the mesh. S to scale it down. G to move, Z to constrain your movements to the Z-axis. Repeat until all your horizontal rings are in place. Each duplicate will automatically be UV unwrapped. When you have all the rings you want, shift-select each and join them with Ctrl + J.
For the vertical rings. You can add another torus, right (Numpad 3) or left side view (Ctrl + Numpad 3), R, 90 to rotate it 90 degrees. Edit mode, mark seams as before, unwrap, move the island off the map somewhere. Scale this along the Z and X-axes—adjust the size as you see fit—delete the bottom faces so that it's a half-circle. Lil' tip here. If you want the bottom edge ring to be even with the ground, hold alt and select the bottom edge, S. Z, 0. The edge will be straightened. Top view (Numpad 7), object mode, shift + D, enter. Rotate, like, 45 degrees (?). Keep duplicating and rotate 40 or 45 degrees (or whatever) till you're satisfied. Ctrl + J to join the meshes when you're done.
For the stars, unhide the original mesh, select and separate one star (press P). Object mode. Hide the old mesh again. Face select. Select the top and bottom and delete (X > faces). Press A to select everything. W > Remove Doubles. Vertex select. Merge the random vertices on the sides with the ones on the ends. Shift select one in the middle, then the one on the end, Alt + M, At Last. Do this will all the extra vertices that are similar.
Shift + alt and select each edge, press T to open the side panel, mark the edges sharp. They will turn blue. Mark one seam on the side as well. This will ensure the sides unwrap as one strip. Press A to select all of the sides, U to unwrap. Move the island off to the side somewhere. Press T to close the panel again.
To add new faces to the star. Vertex select. Hold shift and select three vertices, F to make a new face. Do this to fill in the top and the bottom of the star.
Then select all the new faces you made, top and bottom, U > unwrap. Move the islands off the map. Object mode. You can now duplicate this star and place the duplicates anywhere you want. They will automatically be UV-unwrapped. Join them all with Ctrl + J.
For the beads, add an ico-sphere, mark the seams, unwrap, move the islands off the map. Duplicate to make more. Join them all when done.
Unhide the old mesh. Edit mode. Select the top...cap?...of the mesh and separate it with P. Object mode, hide the old mesh. Select the cap, edit mode, press A to select everything, W > Remove Doubles. Select and delete the top and bottom faces, edge select, shift + alt and select the top and bottom rings, mark sharp. Mark one seam on the side, U > unwrap. Move islands off the map somewhere. Select top ring, E to extrude, move your mouse toward the center, alt + M > at center. Do the same with the bottom. Select the top and the bottom (what you just extruded) and unwrap them. Move the island off the map.
Delete your old mesh. That should go without saying.
After you're done remaking the mesh, Ctrl + J and join everything, move the UV islands back onto the map, vertex paint your mesh, assign the cut number, and
split the edges on the stars and the cap to avoid unsightly shadows (this is why you marked those edges sharp first).
To make the lower LODs, edit mode, edge select, hold shift + alt and select some edge loops, X > dissolve edges. Your mesh will change shape a little with the lower LODs but as explained above, you can't really see the lower LODs anyway.
FIRST, turn your tris to quads. This means fewer edges to deal with. Press T to open the side panel, edit mode, press A, alt + J, put a checkmark next to compare UVs. Sometimes turn tris to quads ruins your UV layout. Compare UVs fixes that. Now, you can start dissolving edges. Keep in mind that Studio will turn the quads back into tris so whatever Blender says your polycount is (at the top of the screen) that number will be double.
Clone a new package and import the meshes and textures again. Make sure you have just one object definition in the warehouse.
If the problem persists, try
removing occluders. And sometimes,
your graphics card can cause problems. Or, it could be that you need to
disable SSAO.
And why not
bake an ambient occlusion map? Your mesh will look a thousand times better.
