Funny enough it seems that it was supposed to be supported already. See here
Unfortunatelly it does not work on v126.96.36.199.
What is worse is that the behaviour of inserting a non-identifying relationship has changed from v188.8.131.52. Like you, I also have tables where the PK is named simply ID, and when I try to create a FK on the other table, instead of automatcly creating a new column named ID, it tries to map the FK to an existing column. It does not care the column has a different name. It doesn't even care if the column type is not the same. Really, really weird.
Only changing the default option to "always show dialog" helps with this issue, but unfortunatelly it is hindered by the fact that we cannot use <%ParentTableName%> to make Toad create a good column name for us.