I just tried to open my old designs which I made somewhat pre-2004 in various versions of Aldus/Macromedia Freehand.
At first I opened only the old PDFs if I had them exported, which worked fine. But then I tried dragging the fh10-file onto Affinity Designer and WOW! this was even better!!!!!
So, I think I better report this here, in case someone searches for this.
Thank you very much, Affinity-team!
(p.s. .fh9 did not work)