irksome > weary; disgusted; also: irksome
6 That troublous dream gan freshly toss his brain
gan > did; began to
7 With bowers, and beds, and ladies' dear delight:
bowers > bedrooms
8 But when he saw his labour all was vain,
he > [the sprite bearing the dream]
9 With that misformed sprite he back returned again.
misformed > {Mis-made; evilly or falsely made. The prefix "mis-" (from Greek misos, hatred, grudge), generally denotes "evilly", "with bad intention", etc.} back > [to Archimago]