I’ve recently tried to open a file in SL12 from SF18 but from the tools menu its greyed out, so I installed SL 11 and there it was, I was able to open SL but it launched SL11. Does SF18 not work with SL12?
Perhaps Magix no longer has licensing with Spectralayers going forward after 11.
What does Magix say when you ask them the situation with Sound Forge 18/sl12 ?