Haste and mana:
We will get 40% of our mana back over 10 seconds with Judgement.
As far as I know that will be on a 7 or 8 seconds cooldown. Let's assume 7 for now.
Every 7 seconds you will refresh your mana return, thus 'wasting' 3 seconds of it.
But haste will make it tick faster, so with enough haste we will get 40% mana over 7 seconds.
Then we refresh it and get another 40% over 7 seconds.
That is how haste improves our mana return.
Without haste: 280% over 70 seconds.
With enough haste: 400% over 70 seconds.
(Numbers might be different, but this is the general idea)
Second question:
30% with every melee swing
And no idea, I hope they fix it.. The ability seems so bad, even now I'd rather use that proc for a 'useless' FoL on somebody.
But the best thing might be to lower the proc and make the talent also refresh the cooldown
PS. Haste will also increase the Censure ticks. Censure is the new dot from Seal of Truth (Former Seal of Corruption/Vengeance)