Smooth movement over seem?

I have a script to generate a world for testing purposes, where I place, (or randomly place), simple cube primitives in a platformer-like way, (creating a 2D game with 3D).

The level I use for testing is a Mario Bros. lvl 1 copy, (it has great elements for testing ). I have a code that uses XY coords, a direction and number of cubes to instantiate in that direction. This works execellently.

My problem is that when my "Player" object moves, and hits a "seem", it does a little "jolt", which looks stupid, but also messes with my movement script. I have trie using other colliders, and I have tried to "soften" the collision detection, but to no avail.

Thanks for the help! Frank

If someone is interested, here's an approximation of my level creation script, (my actual is much more versatile but is copyrighted, by my employer, so I can't share it): using UnityEngine; using System.Collections;

 public class Level : MonoBehaviour {
     //new game objects
     GameObject enviroment;
     GameObject enviromentGroup;
 
     void Start()
     {
         // function to create the predetermened level layout
         // TODO: Allow for variables to trigger the selected level to create
         LoadLevel();
     }
 
     // Method to hold the instruction for creating a level
     public void LoadLevel()
     {
         //Create a parent object for the level
         enviromentGroup = new GameObject("Grouped Enviroment Objects");
 
         // Populate world with cubes
         CreateEnviromentElementCube(-15f, -1f, 25, true);
 
         /* ##### LEVEL BOUNDERIES ##### */
                             // values: X, Y, Amount, Is X-direction?
         CreateEnviromentElementCube(-50f, -50f, 100, true);        // Left Bottom to Right Bottom
         CreateEnviromentElementCube(-50f, -49f, 100, false);    // Left Bottom to Left Top
         CreateEnviromentElementCube(-49f, 50f, 100, true);        // Left Top to Right Top
         CreateEnviromentElementCube(50f, -50f, 100, false);        // Right Top to Right Bottom
     }
 
     // method to instatiate "levelCubes"
     public void CreateEnviromentElementCube(float varPosX1, float varPosY1, int varNumBlocks, bool varBlockDirection)
     {
         // cycle through the given number of blocks in given direction
         for(int i = 0; i< varNumBlocks; i++)
         {
 
             // create cubes in level
             enviroment = GameObject.CreatePrimitive(PrimitiveType.Cube);
             enviroment.name = "Enviroment";
             enviroment.transform.parent = enviromentGroup.transform;
             enviroment.transform.position = new Vector3(varPosX1, varPosY1, 0f);
 
             // add values to iterate one block at desired direction | first block is in the exact given position always
             if (varBlockDirection)        varPosX1 = varPosX1 + 1f;
             if (!varBlockDirection)        varPosY1 = varPosY1 + 1f;
         }
     }
 }