To convert extract % to SG potential, multiply the extract potential by 0.0462 and add one. So for your 78% extract potential, the SG potential is:
0.78 * 0.0462 + 1 = 1.036
The above is the dry basis potential. This malt has 7% moisture, which is higher than the more typical 4%. To convert dry basis to as-is basis you have to multiply the dry potential by 1 - moisture%. So the as-is SG potential of this malt is:
0.78 * (1 - 0.07) * 0.0462 + 1 = 1.0335
I don't know whether BS corrects for dry basis or as-is basis, but not doing so can make your efficiency look lower than it actually is.
My spreadsheet does correct for moisture content. My spreadsheet is not a brewing software suite, but it does a good job of predicting SG and efficiency if you know your malt data and typical conversion efficiency. It corrects for grain bill size effects, and lauter process (sparge or no-sparge.)
Brew on