Here’s my translation

Alan

Ok er Þórðr vissi þat, at hann var þar kominn, þá réð hann til mann at vinna á Sveini. 
And when Þórðr knew that, that he was (had) come there, then he hired (ráða, Z7) a person (man) for [that] (I assumed  <þess> was understood and  <til> was being used elliptically, ie <hann réð mann til þess, at...>] to do-a-bodily-injury (<vinna á e-m>, Z12) to Sveinn.

Sá hét Gísli. 
That-one (ie He) was-called Gísli.

Hann hjó á hönd honum upp við öxl. 
He hewed onto his arm up towards [the] shoulder-joint.

Þá hjó sá maðr, er Guðmundr hét, Gísla banahögg. 
Then that-person (man), who was-called Guðmundr, hewed Gísli a death-blow. (Þórðr won’t be hiring him again!)

Búi hét húskarl Þórðar. 
[The] manservant of Þórðr was-called Búi.

Hann hjó til Guðmundar. 
He hewed at Guðmundr.

Af því sári fekk hann bana. 
From that wound, he (ie Guðmundr) received death.

Nú eftir þenna atburð hafði Þórðr staðfestu í Vatnsfirði ok mannaforráð. 
Now after this incident Þórðr had permanent-residence in Vatnsfjörðr and authority.

Þorvaldr var þá staðfestulauss nökkura vetr. 
Þorvaldr was then (ie at that time) without-fixed-abode for several winters.

Sveinn var færðr til lækningar þeim manni, er Þorbjörn hét, ok varð eigi græddr, fyrr en Hrafn græddi hann. 
Sveinn was brought (presented) for medical-treatment to that person (man) who was-called Þorbjörn, and-yet (but) became not healed before Hrafn healed him.

Síðan fór Sveinn í brott af landi ok gerði bú á Hálogalandi ok kom eigi síðan til Íslands.
After-that Sveinn journeyed away from [the] land and built a home in Hálogaland (Heligoland) and came not after-that to Iceland.

9. Frá Magnúsi presti ok vígi Ljóts.
9. About Magnús [the] priest and [the] slaying of Ljótr.

Magnús hét prestr. 
[There] was a priest called Magnús.

Hann var Þórðarson, Þórissonar, er kallaðr var Tolla-Þórir. 
He was [the] son of Þórðr, son of Þórir, who was called Tolla-Þórir.

Magnús gerði eftir Jórunni Snorradóttur til Ísafjarðar ok hafði hana með sér í Dýrafjörð á Mýrar. 
Magnús sent for (ie picked up and brought, <göra eptir e-m>, Z13) Jórunn Snorri’s-daughter to Ísafjörðr and brought her (hafa, Z6) with him to Dýrafjörðr (Fjord of wild animals) in Mýrar (Swamps)

Þar bjó sá maðr, er Mögr hét. 
There dwelt that person (man), who was-called Mögr.

Hann var Mögsson, en Magnús var þar heimaprestr með honum. 
He was [the] son-of-Mögr, but (and) Magnús was then resident-priest with him.

Bergþórr hét maðr Sámsson, Brandssonar. 
[There] was a person (man) called Bergþórr, son-of Sámr, son-of-Brandr.

Hann hafði nökkut verit fyrr í tíðleikum við Jórunni, ok er hann frá, at Magnús prestr hafði eftir henni gert, þá fór hann til Dýrafjarðar ok ætlaði at hafa Jórunni brott með sér. 
He had, to-some-degree, earlier, been in-courtship with Jórunn, and when he heard (not falling for that again!), that Magnús [the] priest had sent for her, then he (ie Bergþórr) journeyed to Dýrafjörðr, and intended to bring Jórunn (acc so <Jórunn> must be jo-stem noun) away with him

En fyrr en Bergþórr kæmi á Mýrar, þá var Magnúsi sögð för hans ok fyrirætlan. 
But (And) before Bergþórr might-come to Mýrar, then his journey (nominative) was said (ie reported) to Magnús (dative) and [its] purpose.

Þá lét Magnús prestr flytja Jórunni á þann bæ, er at Gnúpi heitir, ok var hon þar varðveitt á laun, meðan Bergþórr var þar í heraðinu. 
Then Magnús [the] priest caused to convey Jórunn to that farm, which is-called at Gnúpr (Peak), and there she was kept in secret, while Bergþórr was there in the-district.

At Gnúpi bjó kona sú, er Sigríðr hét. 
At Gnúpr dwelt that-woman, who was-called Sigríðr.

Hon var Þórðardóttir. 
She was [the] daughter-of-Þórðr

Hon var góð húsfreyja ok fengsöm.
She was a good mistress-of-the-house and [one] making-large-provision (ever-stocking-up).

Bergþórr kom á Mýrar ok var þar við honum vel tekit. 
Bergþórr came to Mýrar and [it] was there well-taken with him (ie he received a good reception there).

Þar var hann nætr nökkurar ok gat eigi upp spurt Jórunni. 
He was (stayed) there several nights and was-not-able to track down (lit: up) (much the same as <find out about>) Jórunn.

Magnús var við Bergþór allkátr ok gaf honum hund, er hann fór á brott. 
Magnús was very-merry with Bergþórr and gave him a dog, when he journeyed away.

Bergþórr fór heimleiðis, ok var Jórunn eigi í ferð með honum. 
Bergþórr journeyed homewards, and Jórunn was not in [the] journey (ie did not travel) with him

Þá kvað Magnús vísu þessa:
Then Mágnus recited this verse.

[Option A] 

   Sitr fimligt fljóð,
[The] nimble woman sits

   fram greiðik ljóð,
I arrange forth a verse,

   vex greppi sút,
Grief grew in the doughty-man (<greppr>, Z2),

   und Gnúpi út.
out under Gnúpr.

   En hafði heim,
But [he] brought home

   þats hæfði þeim:
that-which [I] would-have for that-one (ie him)

   Vas hundr í för
A dog was in [the] journey

   með hjalma bör.
with [the] son of helmets (presumably <hjalma>= <hjálma>) (ie warrior)

[Option B]   [No option B]

[Option C]

   Hin mjúklega vaxna kona situr heima úti undir Niípi. 
The nimbly shapen woman sits at home outside under Gnúpr (Niípr)

   Eg yrki vísu. 
I make a verse.

   Manninum vex áhyggja. 
Anxiety grew in the person (man).

   En hann hafði það heim með sér, sem hæfði honum: Hundur var í för með kappanum.
But (And) he brought (hafa, Z6) that home with him, which [I] would-have for him (ie which I wished for him to have): A dog was in [the] journey with the-hero.