You mentioned in your post that you are doing Extract Brewing. As long as you are doing extract brewing, you should not need to input much for the Equipment Profile. This is particularly true for the Mash Tun parameters -- because you are not using a Mash Tun. Simply indicate the size of kettle that you are using and you will be fine. You can do this by choosing a kettle profile from the program, and adjusting it for your purposes.
The reason that you can get away with this is because you are not really worried about Mash Tun volume, pounds of grain in the mash, water volume, the amount of heat that the mash tun will suck out of the hot mash when you mash in, the amount of water left in the mash tun (dead space) after the mash is drained, etc. All of that has to do with All Grain brewing, and you can adjust these parameters when you step into All Grain.
However, when entering your recipes, you will want to make sure that you indicate that the recipe is an extract recipe. I think you have three choices, extract, partial mash, and all grain. So, as long as you are extract brewing, and I think that this is a good way to begin and will give you an opportunity to become more familiar with the program, you will not really need the equipment profile. When you move up to partial mashing and all grain brewing, the equipment profile becomes much more important in allowing BeerSmith to calculate strike water temps, etc. I hope that this helps.