When you save after adding a new talisman it will show a popup window that tells you how many new talisman were created; was the number reported as expected?
If you load the edited save back into the editor, do you still see the new talisman?
In terms of location, new talisman are always created in the next empty slot in your equipment box, and depending on how your equipment is organized it may appear in a not so obvious position.
I'm still on box 1 and I auto sort my equipment box so talismans would be the last items on the box. I've edited one talisman and created one more from scratch but when I save it states only "1 new".