Cris -- BMR generally consists of the calories spent to just keep you alive! So, what you would burn if you slept all day and night or were in a coma, that sort of thing.
Nutridiary claims that when you add activities, it is in addition to BMR
One caution -- online calculators seem to typically estimate on the high side for calories burned. In some cases, quite high.
What I do in nutridiary is set my lifestyle as lightly active, even though many days I am more active than that. Then the only exercise I enter is the exercise I count for my minutes (elliptical, weights, some heavy yard work).
In the past, I've been lucky and this combination, along with counting calories has produced good estimates for weight loss. Other people find the estimates to be high or low for them.
I don't know if I answered your question or just blathered a bunch!!