Set intersection issues, strict adherance to data serialization type?

Gather that this occurs due to the serialization status of the set?:

This was the data I was looking for - basically an index map to check against a second set of indices from a r-tree component:

I thought that the data was messed up, but could manually find the objects in the branch.

Putting a panel in the middle seemed to fix it:

Can also use an number comp, as the panel seems to slow down the definition:

The retree is my component, but behavior is still null if series is passed straight to SetInt:

How does an index and an number differ? There should be some ability to exchange these data types, sort of like line to vector to brep passed directly into a mesh component.

I understand that the output of series is technically float, but inverse is possible, i can take float numbers and auto round to nearest: