BudiBase invalid error when creating relation for MySQL using a relationship table

[vbonachuck-sr]

Hello everyone. Hope this is a straight forward question. We thought we would try building a form with budibase to maintain the some of master the tables in our MySql db as a quick internal data maintenance solution. The database is fully normalized and there are main tables and relationship tables.

master_material = has all materials
master_information = has all related information about any given material
master_material_information = has the relationship data. A given material may link to 1 or more information records

I'm getting an error in BudiBase which I cannot figure out why that is:

I believe I am matching the requirements, all non-primary key fields as nullable as per screenshot below:

What am I missing here?? Really appreciate any help I can get on this!