Continuity mistake: When Adama is trying to resign the President hands him a copy of the certificate she wants to present to him. The pen that was in the holder a few seconds ago has been removed to allow her to hand it to him without the pen in the way. (00:39:00)
Continuity mistake: In the scene where Apollo and Helo are boxing, Helo punches Apollo and this cause his head to bleed down his face. A few shots later the stream isn't as long.
Chosen answer: Her motives are never explained. One possibility would be curiosity, a simple experiment in human infant physiology. Another, perhaps more likely one from her subsequent look of apparent distress is that it was, in an odd way, an act of mercy, giving an innocent baby a swift death, rather than leaving it to die in the nuclear fire or of radiation poisoning afterwards.
Tailkinker ★