Here’s my translation
Loftr kom eftir jólin vestr á Mýrar í Dýrafjörð at ráði Sighvats Sturlusonar ok Eyjólfs Þorsteinssonar.
Loptr came after the-Yule west to Mýrar to Dýrafjörðr according to (ie on) [the] advice of Sighvatr Sturla’s-son and Eyjólfr Þorsteinn’s-son.
Ok er Þorvaldr frá, at Loftr var kominn á Mýrar, safnaði hann liði ok fór á Mýrar með fjölmenni.
And when Þorvaldr heard that Loptr was (had) come to Mýrar, he gathered troops and journeyed to Mýrar with many-people.
Til þeirar farar spurðu vinir Lofts, ok söfnuðu þeir liði ok kómu á Mýrar, þá er Þorvaldr var kominn þar, ok leituðu um sáttir á milli þeira Þorvalds ok Lofts.
[The] friends of Loptr heard-tiding of that (<þeirar> not <þeira>) journey, and they gathered troops and came to Mýrar, when Þorvaldr was (had) come there, and tried to get agreements between them, Þorvaldr and Loptr.
Ok fyrir því at Þorvaldr sá, at Loftr hafði þar fleiri fulltingsmenn, þá sættist hann við Loft ok fór í brott síðan.
And for that that (ie because) Þorvaldr saw, that Loptr had there more supporters, then he came-to-terms with Loptr and journeyed away after-that.
Ok er hann var í brott, treystist Loftr eigi at vera á Mýrum, því at honum þótti einskis örvænt fyrir Þorvaldi um tiltektir.
And when he was away, Loptr dared not to be (ie stay) in Mýrar, because [it] seemed to him beyond expectation of nothing for Þorvaldr concerning what-[he]-undertakes-to-do (ie Þorvaldr was thought capable of anything, anything might be expected of him)
Loftr fór þá til Hrafns á Eyri ok bað, at hann skyldi taka við honum, kvað Sighvat hafa sent honum orð til ásjá við sik, en í þann tíð var Sighvatr mikill vinr Hrafns.
Loptr journeyed then to Hrafn at Eyrr, and asked, that he should receive him, declared Sighvatr to have sent him (ie Hrafn) word (ie a message) in respect of help towards himself (Loptr) (ie advocating Hrafn´s support for Loptr), but (and) at that time Sighvatr was a great friend of Hrafn.
Nú fyrir því at Hrafni var leitt at kveða nei við þeim, er hans þurftu, þá varð þat, at hann tók við Lofti.
Now for that that (ie because) [it] was disliked by Hrafn (ie Hrafn disliked, <leiðr>) to say no to those, who stood-in-need of him, then that came-to-pass, that he received Loptr.
Um þat sannar Guðbrandr:
About that Guðbrandr affirms:
Betr vill ægis otra
better wants, of [the] sea of otters
oft, tók Hrafn við Lofti,
often, Hrafn received Loptr.
raun sannar þat, rennir
Experience proves that, [the] runner (<rennir> Lex Poet)
ráðgjarn hafa en aðrir.
ambitious to have (win <hafa>, Z8)) than others
B: Ráðgjarn ægis otra rennir vill oft hafa betr en aðrir. Raun sannar þat. Hrafn tók við Lofti
(re-ordering the above: [The] ambitious seafarer (lit: runner of the sea of otters, <rennir ægis otra>, (Lex. Poet.) wants often to win better (ie succeed more, <hafa betr>, Z8) than others. Experience proves that. Hrafn received Loptr.
C: Hinn heilráði sæfari vill oft koma betur fram en aðrir. Reynslan sannar það. Hrafn tók við Lofti.
(modern Icelandic) The wise-counselling sea-farer will often come forward (emerge, succeed) better than others. The-experience proves that. Hrafn received Loptr.
Ok er Þorvaldr frá, at Hrafn hafði tekit við Lofti, þá mislíkaði honum við Hrafn sín tiltekja fyrir óþykktar sakir þeirar, er milli þeira Lofts váru.
And when Þorvaldr heard, that Hrafn had received Loptr, then his (? See note below) actions displeased him towards Hrafn (ie Hrafn´s interference displeased him) for [the] causes of that discord which were (ie existed, agrees with <sakir>) between them, Loptr (and himself).
Note: <sín tiltekja> has me stumped: <tiltekja> can only be nom fem sg and <sín> would, following the usual declining of possessive pronouns, theoretically be the nom fem sg of the reflexive possessive pronoun <sinn>, and thus agree with <tiltekja>, except that reflexive pronouns shouldn´t have a nominative form.
Eftir þat sendi Þorvaldr Hrafni orð, at hann skyldi koma til fundar við hann í Dýrafirði á þann bæ, er á Granda hét.
After that Þorvald sent Hrafn word (a message), that he should come to a meeting with him in Dýrafjörðr at that farm, which was-called at Grandi.
Þangat kom Hrafn við inn þriðja mann fyrr en Þorvaldr ok beið hans inni.
Thither came Hrafn with the third man (ie with two others) before Þorvaldr, and (Hrafn) waited for (<bíða>) him in-doors.
Ok er Þorvaldr kom, við marga menn, þá sendi hann orð Hrafni, at hann skyldi út ganga.
And when Þorvaldr came, with many persons (men), then he sent word to Hrafn, that he should go (step) outside.
Þá gekk Hrafn út ok hans förunautar, Tómas Þórarinsson ok Sturla Bárðarson.
Then Hrafn went (stepped) outside and his travelling-companions, Tómas Þórarinn’s-son and Sturla Bárðr’s-son.