miles,
The blinds thing in the Calculator is the way you set the ratio of the buyin to the small blind. That's only used by the Recommend! button to determine what the smallest denom needs to be. If you're manually tweaking the starting chips/player, you can ignore the blinds thing.
So for your cash game, with a $50 buyin and a small blind of $.50, you'd set the blinds ratio to 100xSB ($50/$.50 = 100). Then you'd set the number of players and # of rebuys, and push the Recommend! button to see what it suggests. Then you can over-ride any of the values it suggests, if you don't like them.
For example, for your cash game, you could go with this:
For your tourney, you could go with:
Combining those two games in the Game Variety Window yields:

Note in this case, though, that you'd be using $25 chips both in the tourney and for rebuys in the cash game. So if you had both games going on at the same time, you'd need more $25 chips. Or maybe you're planning two different sets for these games?
Anyhow, hopefully that will give you a starting point and you can tweak away from there.