Congratulations on adopting such a pretty girl. Maggie looks great, I wish you guys the best with her. The piggie sure looks like hes been eating well, ehehehhehe,
Good looking pig. 
As far as thumping its usually used a a warning, when they are fearful of something. And can also thump when angry .
Heres an explanation I found on a bunny site.
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Thumping
Rabbits stand on all four feet, in a somewhat tip-toe position, with their ears alert, then lift their rear feet and thump! to warn everyone in the warren (including humans) that there is "danger," in the rabbit's opinion.
They may remain in the thumping posture until convinced that the danger is gone. The length of time between thumps can vary from a few seconds to a couple of minutes and may last an extended period of time (even an hour or more).
This "danger" could be a furnace, refrigerator or other electrical appliance turning on or a lit cigarette when they are not used to the smoke.
"Danger" could be the shadow of a bird flying across the moon or a cat walking on the window sill chasing a shadow on the floor. Thumping can occur day or night and is the rabbit's attempt to save everyone from a terrible fate.
A rabbit who is exhibiting continual thumping can die from fright and should be reassured and comforted as soon as possible.
As an expression of anger, I am sometimes given a thump when I return a rabbit to his cage after an exercise period. He either doesn't want to return (thump!) or would rather do it himself (thump!).
When not at all pleased with what has just happened, a thump is often in order. For instance, when he thinks he should have another piece of fruit, and instead, I eat it myself (thump!).
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So there ya have it, LOL Good luck with Maggie, keep the pics coming we love them.
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Eve / PHEve
