So, here's what I learned:
- Online and offline savegames are mutually incompatible.
- You cannot get quicker to the same point using cheat codes ... because there are none! (Thank god at least you can use automatic combats to speed it up a little bit...)

Did I get that right?

If I did, why did Ubisoft settle on such an idiotic system? I'm really tempted to try to get a refund now...