Try the following
0. Make sure TotF.esp is last in load order.
1. Load your saved game.
2. Call console (~), type
message "%0.f" ZZTheLegacy2.AlleciaWantsToTalk
press
3. There'll be a number in top left corner of the screen. If it's 1 (as I suppose it to be), follow next steps of the instructions. Otherwise tell me.
4. You should still be in the console (otherwise enter it), so type
set ZZTheLegacy2.Dialogue4 to 1
press
set AlleciaDialogueCounter to 4
press
5. Talk to Allecia now. She will tell one of her previous dialogues. Though since you were using an old version, this dialogue may be new for you. Anyway, keep in mind that this discussion should have occured before you finished The Legacy, so don't be surprised if she says something weird.
At the end of that dialogue everything should turn alright, quest variables and conditions and everything, and next time you address her she should have normal companion options.
Hope that helps. If anything goes wrong, return here.
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