Mash Tun Deadspace question

Hello Everyone,
I'll start by saying how much I enjoy BeerSmith and this forum. This is my first time posting and I am somewhat new to all-grain (or any) brewing. I have ~70 gals under my belt.
I have a question about configuring equipment in BeerSmith. I use three 15.5 gal kettles for 11 gal batches. My MLT has a false bottom with diptube extending down through FB, drawing wort from bottom center of MLT. As a result I have very little deadspace (wort left behind). However, I must account for ~1 gallon of wort below false bottom that is not in contact with grain during mashing. My thinking is this directly affects my water/grain ratio above false bottom if I use my MTL deadspace (.05 gal) output calculations. Is there a recommended way to configure BeerSmith equipment to account for the water below false bottom during mash.
I know I could adjust grain/water ratio or just always add one gallon to account for this but I would rather build into equipment profile so that I don't forget when I decide to do a 5 gal batch.

Many Thanks

Dead space is configured in your mash equipment profile.  Dead space is generally though of as a strike/mash water scaling value.  I think it also affects your overall mash and gravity target.  Calculating estimated gravity from the grain potential without considering the dead space seems that you would be under your target gravity as you are going to use more sparge water to achieve your preboil volume. Assuming I am leaving behind 10-15% of my preboil volume, I often add some extra base grain to account for my estimated loss. 

I have not researched this not have I tried to calculate the actual potential gravity differential.  I just wing it and convince myself it sounds good so why not.  Not typical for me but somethings just don't matter that much.

Dead space in the sparge is water that will not come out of the sparge into the Boil.  Take a basic recipe, change dead space to zero, print out the brew sheet.  Change the dead space to 1 gallon and print out that brew sheet.  You will notice the difference in the gallons of water to prepare and the sparge volume.  It will not change your water into the mash.  This is a value that you can adjust to tune your equipment.  Accurately measure what goes in and what come out and use this value to adjust until Brewsmith gives you the same predicted values as the ones you measured. 

As far as how it will effect your effective grain to water value and the resulting conversion efficiency I don't know.

David