No. That is the prosecutor's fallacy; the statistic describes profile rarity, not the probability of guilt or innocence.
A comparison of how probable the evidence is under two stated propositions, showing which explanation the evidence supports more strongly.
Several contributors and small amounts of DNA create ambiguity, so results can vary by method and some are reported as inconclusive.
Yes. Relatives are more likely to share DNA, and standard statistics for unrelated people may not apply to them.
No. It does not show when, how or why DNA was deposited, which must be assessed using other evidence.