Help needed with DAX Switch Statement multiple columns (Picture included)

Suggest you create the table I suggested (Region, Lower Limit, Upper Limit, Rating) for one region as a test. This will have 5 lines in it.  Just type it in in 'Enter Data'

Then, in the other table, create a column which returns the rating.

Obviously if you get it working it will only return a rating for the region you have in the first table but you can then expand the first table to cover all regions.

Here is a similar post

https://social.msdn.microsoft.com/Forums/sqlserver/en-US/d8e66abd-c383-4234-a8cf-8406bbe64ce2/if-dax-statement-between-two-values 

. Look at the DAX in the answer post . 

Yours may look something like this.

Let me know how it goes.