Here’s my translation

Alan

3. Frá Hrafni ok íþróttum hans.
3. About Hrafn and his accomplishments.

Hrafn var á unga aldri snemmendis mikill atgervismaðr. 
Hrafn was, early in [his] youth (unga-aldr), a great person (man)-of-great-[physical]-accomplishments.

Hann var völundr at hagleik, bæði at tré ok at járni, ok skáld, þó hefir hann fátt kveðit, svá at vér vitim, ok inn mesti læknir ok vel lærðr ok eigi meir vígðr en krúnuvígslu, lögspakr maðr ok vel máli farinn ok at öllu fróðr. 
He was a masterful-exponent of skill-in-handicraft, both in wood and in iron, and a [scaldic] poet, though he has [composed and] recited so little (<kveða>, Z2) that we know, and the greatest physician and very learned and not more ordained than with [the] ordination-of-tonsure (coronation, <krúnuvígsla>, CV, but here I´m guessing that this refers to something akin to ‘first tonsure’ or ‘monastic coronation’ depending on practice?), a person (man) learned-in-law (lit: law-wise) and well-spoken (eloquent, cf, <vel orði farinn> under <farinn> Z2) and well-informed in all [respects].

Hrafn var mikill maðr ok réttleitr í andliti, svartr á hárslit, syndr vel ok við allt fimr, þat er hann hafðist at, bogmaðr mikill ok skaut manna bezt handskoti. 
Hrafn was a large person (man) and regular-featured in face, black in hair-colour, well able-to-swim (ie a good swimmer) and agile (adj) regarding (<við>, Z.ii.6) all that which he did (<hafast at>, Z15), a great bowman and, of people (men), in throwing-by-hand, [he] shot best.

Hrafn fór ungr brott af landi, ok fekk góða virðing í öðrum löndum af höfðingjum, sem vitni bar um þær gersimar, er Bjarni byskup sendi honum, sonr Kolbeins hrúgu ór Orkneyjum, út hingat, þat fingrgull, er stóð eyri, ok var merktr á hrafn ok nafn hans, svá at innsigla má með. 
Young, Hrafn journeyed away from [the] land, and obtained a good reputation in other lands from men-of-rank-or-authority (<höfðingi>, Z3), to which those treasures bore witness, which Bishop Bjarni, son of Kolbeinn hrúga (heap, a nickname, <hrúga>, CV2) out-of [the] Orkneys, sent him, out hither, that finger-ring-of-gold, which weighed (or was worth (see <eyrir>, Z1) an ounce, and a raven and his name was marked on [it], so that [he] can seal (ie make his seal) with [it].

Annan hlut sendi byskup honum, söðul góðan ok inn þriðja hlut steinklæði. 
Another thing [the] bishop sent him, a good saddle and the third thing coloured (ie stained, pp of  <steina>, Z1) clothes (=steintklæði).

Hrafn var utan einn vetr ok var á hendi tignum mönnum ok þótti mikils verðr, hvar sem hann kom, fyrir íþrótta sakir. 
Hrafn was abroad one winter and was in [the] charge (ie under the protection, <hönd>, CV B.1) of noble persons (men, plural) and [he] was-thought worthy of much (ie he was highly valued), wherever he came, for reasons  (ie because) of [his] accomplishments.

Þá réð Sverrir konungr fyrir Nóregi. 
Then (ie at that time) King Sverrir ruled (ie had authority over) Norway.

Annat sumar sigldi hann út hingat ok fór til bús með föður sínum á Eyri.
[The] next summer he sailed out hither and journeyed to [the] farm with his father at Eyri.

4. Utanför Hrafns ok frá lækningum hans.
4. Hrafn’s journey-abroad and about his healing-arts.

Atburðr sá gerðist í Dýrafirði á várþingi, þá er Hrafn var þar, at rosmhvalr kom upp á land, ok fóru menn til at særa hann, en hvalrinn hljóp á sjó ok sökk, því at hann var særðr á hol. 
That event happened (ie it came to pass) in Dýrafjörðr (Wild-beasts’-fjord) at [the] spring-assembly, when Hrafn was there, that a walrus came up onto land (ie ashore) and people (men) journey to [it] to wound it, but (and) the-walrus (lit: whale) leapt into [the] sea and sank, because it was wounded in [its] [body] cavity.

Síðan fóru menn til á skipum ok gerðu til sóknir ok vildu draga hvalinn at landi ok unnu engar lyktir á. 
After-that people (men) journeyed to [it] in ships, and [they] made attacks (plural) towards [it] and wanted to drag the-walrus (lit: whale) to land (ashore) and [they) effected, (<vinna e-t á>, Z12) no conclusions (plural) (ie they were unsuccessful).

Þá hét Hrafn á inn helga Tómas byskup til þess, at nást skyldi hvalrinn, hausfastar tennar ór hvalnum, ef þeir gæti nát hvalinn at landi fluttan. 
Then Hrafn appealed to (invoked) the holy bishop Tómas to that [end], that the-walrus (lit: whale) should be-caught, tusks (tönn, Z2) seated-in-the-skull [extracted?] out-of the-walrus (lit: whale), if they were-able to get the- walrus (lit: whale) conveyed (masc sg acc of pp of <flytja>) to land (ashore).

Ok síðan, er hann hafði heitit, þá varð þeim ekki fyrir at flytja at landi hvalinn. 
And from the time when (<síðan er, Z4>?) he had appealed (<heita> Z2 with <á e-n…> understood), then [it) befell them not before to convey the- walrus (lit: whale) to land (ashore). (ie The exact sense of <síðan er> is unclear to me but the overall sense seems to be: they were unable to convey the walrus ashore until after Hrafn had made his appeal to Tómas)

Þessu næst fór Hrafn í brott, ok kómu þeir skipi sínu við Nóreg. 
Thereupon Hrafn journeyed away, and they brought their (reflexive pronoun so must refer to the subject <þeir>) ship to (lit: against, [the coast of] Norway.

Þetta sannar Guðmundr Svertingsson í drápu þeiri, er hann orti um Hrafn:
Guðmundr, son of Sverting, affirms this in that drápa (poem in praise of heroic deeds, demonst art and noun are both dat fem sg), which he worked-up (ie composed) about Hrafn.