Have no idea how something like the grainfather works regarding water requirements. But I'm guessing you could use a BIAB calculator and it would be somewhat close. I don't know how much water+grain one of those can hold at once.
This is the one I use:
http://pricelessbrewing.github.io/BiabCalc/
But looks likes they have their own, so I'd use that:
http://www.grainfather.com/#!brewing-calculator/cljs
As for the yeast, I'd really recommend using WY1968 and making a starter. You say you don't have the equipment, you don't need any to make a starter. You need some DME and a stove pot, and then some sanitized container to put the starter wort in (I use glass growlers, but you could even use a 2L soda bottle.) It's a very easy process and takes 20 mins or so the day before you want to brew. A stirplate/flask makes the most powerful starters, but just a starter sitting there on the counter is much better than none. I go by and give mine a swirl every time I walk by, and that's worked very well.
I do not care for the S04, others have had better luck. If you REALLY don't want to make a starter, you could pitch 2 packs of the WY1968.