Ill-legal block?

[Juxone]

Two simple questions ( are they really ever simple) (Federation rules)

Eligible Receiver runs 15 yards down field, hitting defender knocking defender to ground, cuts and runs down field as ball is thrown --- legal contact or not?

or does ART. 10 apply . . . It is forward-pass interference if:
a. ANY PLAYER (my emphasis) of A or B who is beyond the neutral zone interferes with an eligible opponent's opportunity TO "MOVE FORWARD" (implied or), catch or bat the pass.

Second situation:
K kicks the ball during opening kickoff, ball goes 40 yards. two K players make contact with return team BEFORE ball is touched? Illegal block?