When I was going to use Happy, I was going to retrieve her from the bin and reuse her from scratch again. Like I'd just created her, and without any skills etc. But I didn't, because I decided on different traits. I shall always create a new sim from scratch for all future challenges just so as not to break any rules.
Anyhow, I was only trying this for fun, but have run into a small problem trying to max the WA skills. I'm not that versed in WA, and didn't realise that one of the martial arts challenges was to win a tournament. Also sparring could be difficult when the sim returns home, as no-one else in the original town has any martial arts experience. I'm really sad, because it was all going so well. I think if you do rehash this challenge to include WA skills, it will have to have specific guidelines regarding the martial arts challenges. I'm not sure if photography has country specific challenges, as I've never really tried it out, but that may need some investigation too. So I gave up, and will wait for an official relaunch, if and when you can iron out all the potential headaches WA skills pose. I think the original idea for the challenge was awesome. I shall try a different challenge until nectar making on 22nd January. I'm glad your not making serving nectar part of the challenge. Even with the 'Legendary Host' reward, I suspect my parties would still suck.
