I am trying to do a similar repair to a trip hazard and cannot allocate these products - Ultrabond 2100 and Miracle Bond 1310? Does anyone know what suitable replacement products could be used instead?
When applying the Lanko 136 onto the existing concrete or over Lanko 189 you need to ensure the area is clean from contaminants and you'll need to soak the area with water before commencing.
With Lanko products and likewise the products in the video if the slab is still in the process of shifting they will crack and separate. You can certainly patch these cracks once the slab has stopped shifting though.
Please let me know if you require further advice or had any questions on the process.