Has anyone done any joins to multiple records before on Suite Analytics? I am trying to get to 2 different records from an opportunity, a custom record and an attached transaction, i can get to both - just not at the same time as it seems to unlink the first one...

Your problem is most likely that applied transactions exist only at the header, not at the line level

Both were at header level, but i managed to figure it out, it will let you do one record join, then unlink it and link to a different one, was just strange as its not my normal way of doing it and takes a little longer to complete