@oshizu thanks, I was almost sure using the park's grill was ok, but then got confused the more I thought about it! As to my challenge... well, I decided to unlock the restrictions that annoy me the most rather than powering through it so my 'strategy' may or may not work out.
Another question, what are the aging settings for townies supposed to be set at? The only post I could find was where Pinstar said he didn't make any ruling on this. Part of me want to have 'no aging' as I
love having townies in my game but that feels very, very cheaty. Mainly due to there being a few townies that I could see being useful later in the challenge due to their skill levels.
Then again, I suppose that is no different to exporting skilled sims in once that restriction is unlocked, which I also don't intend to do as that feels quite 'cheaty' too. Argh... the decisions!