IBU calculations in Beersmith don't match recipe sheet

Just as a start, middle doesnt mean middle, though Im guessing because I haven't seen that recipe, but I'll take a look, Every single recipe in every book or online will need adjusting unless its been specifically written with our same BS profiles. Even then hops Alpha Acids etc will differ too, so there is always some adjusting. I'll check it out for you

lucked out on the middle lol thats where most get it wrong.

So I threw everything in, I think the 60min needs halving, whether thats a mistake or because they will have very different outcomes in different systems. The 60min does seem extremely large at 75g, I've been doing IPAs with a third, actually less than a third of that. So my recommendation so we're following more to their stats is to get to most like 2/3 of the bitterness from the 60min and the rest will come from the whirlpool. Although I do need to ask whether you plan to do a hot steep at the end or an under 80c one. I normally do hot steeps so thats whats in the recipe, if you do cold steeps up the 60min to get to the 67 Ibus because the rest won't add bitterness. Hope that makes sense, let me know. You need to right click the link below to save/open it. Cheers!

This gunna be a big beer! Thats a lot of galaxy! Blows my mind hahaha

Yep it can, its a rough estimate because its hard to tell what you'll get