Hi,
I don’t think anyone will be able to “just help” you with ELK. This is huge topic. Do you have specific problem or just hoping for “how to- step by step” instruction.
There is a topic about Splunk and Mikrotik, you may want to check it if looking for inspiration: http://forum.mikrotik.com/t/tool-using-splunk-to-analyse-mikrotik-logs-3-3-graphing-everything/121810/1