I use BrewPal and really like it.
The link you posted doesn't show weights of ingredients, but I assume there is some specific information that actually came with the kit. Or at least I would hope so.
If you have that, then just start inputting that ingredient list. If an ingredient isn't already in BrewPal, do a quick google search to find the info (ppg and color rating). If you don't want to do that, just take a guess and get it close.
It is a really nice app once you get used to it and find all of the adjustments you can make. It lets you control just about every aspect of the recipe and calculations.
Just one thing to be wary of, if you are doing an extract with specialty grains type recipe, it will predict a higher OG than you will actually get. That is because it will calculate the specialty grains as contributing the same amount they would in a mash. But because they are just getting steeped, they won't contribute that much fermentable sugar.