> Farið þér til móts við Þórhöllusonu er þeir eru sendir til
> Helgafells að stefna liði að oss.

> Go to meet with Thorholl's sons, who they are sent to
> Helgafell to summon troops against us.

> You go to meet with Thorhall’s sons when they are sent to
> Helgafell to summon men against us.

> Go-you to a meeting with Þórhalla’s-sons when (?) they
> are-sent to Helgafell to assemble a force against us.

I'd make it 'when', despite the MM&HP translation; for that
I'd have expected <er sendir eru til ...>.

> Vel líkar mér þótt þér skapið þeim slíkt víti sem yður
> líkar."

> I am well pleased even though you punished them as you
> please."

> It pleases me well that you shape such punishment for them
> as you wish.”

> (It) pleases me although you create (devise) (present
> tense) for them such punishment as pleases you.”

In other words, I don't care how you do it; just do it!

> Þeir hafa veður lítið og hagstætt.
> They have a light and favorable wind.
> They have little wind and (mostly) favorable.
> They have little wind and favourable.

I like Rob's version here.

> slægist

> (sláast, Z8?)

Yes.

Brian