Help with ProMash efficiency calc

Yesterday I brewed a PM recipe that used 7 lbs of grain and 2 lbs of DME. I've never had stellar efficiencies - typically about 65% - but based on yesterday's results I wonder if I've been using ProMash correctly.

At 65% and 5.0 gal batch size ProMash predicted 33 points from the mash and 18 from the DME, target gravity of 1.051.

I hit an OG of 1.050 but had a final volume of about 5.3 gal so I understand that if I were to boil longer, I'd have a higher OG. But what I don't get is ProMash said that I got 40 pts from my mash and calculated my efficiency at 78%. But if I got 40 pts from the mash then that means I only got 10 pts from the DME and extract should always be 100%. So what gives?

SP

I ran your numbers and here is what I found.
Batch size set at 5.3 gallons.
7 lbs. american 2 row @ 1.036
2 lbs of DME @ 1.046.
At 69% efficiency to achieve 1.050.
If you remove the DME OG becomes 1.033. Looks like there were 17 pts. from the DME.

Yep, ProMash calculated 18 pts from DME for my recipe. But where I'm confused is with the efficiency specifics portion of the session report.

It says:
*******************************
Actuals achieved were:

Actual Points From Mash: 39.65
Actual Mash System Efficiency: 78%
*******************************

It got this from me entering an OG of 1.050 and a final volume of 5.3. So if my points from the mash were 40, then that means my DME contribution was 50 - 40 = 10. How can that be?

SP

I don't use that portion of the software much but the efficiency changes dramitically when measurement taken in fermentor is checked. But I did notice that the points from extract was 17.36 which sounds about right and did not change.