Here’s my translation

Alan

Sigrgarði þikir vel á horfast ok verðr þetta þeira samkeypi. 
(It) seems to Sigrgarðr to look good (promising, ie to bode well) and this becomes their bargain

Fara nú í launkossar en jungfrúinnar orð eru svá fögr sem þau væri ór rauðu gulli gjör öll, ok var mjög áminnandi, at allir skyldu vera sem glaðastir ok gleðja Sigrgarð ok hans menn, ok segist ætla þenna mann sér til unnasta, en þeir menn sem kunnigt var hennar skaplyndi grunaði nökkut hvárt hennar gleði mundi góðu reifa. 
Secret-kisses (nominative plural) now occur (lit: go in, see fara í, Z18) but (and) the-princess (lady)’s words are as fair as if they were all made out of red-gold, and (she) was very reminding (ie kept reminding everyone (with a hint of warning)), that all (ie everyone) should be as glad-as-possible and gladden Sigrgarðr and his people (men), and (she) says-of-herself to intend this person (man) (to be) a lover to her, but (and) those persons (men) who were versed-in (ie familiar with, kunnigr, Z2) her disposition, doubted somewhat whether her gladness would result in (reifa, Z4) good (ie turn out well).

En mönnum Sigrgarðs þótti vel á horfast ok váru inir glöðustu, ok leið svá dagrinn til kvölds. 
But (and) to Sigrgarðr’s people (men) (it) seemed to look good (promosing ie to bode well) and (they) were the most-glad, and so the-day passes towards evening.

Var þá mönnum Sigrgarðs fylgt at sofa, með sæmiligum umbúningi. 
(It) was then guided for Sigrgarðr’s people (men) to sleep (ie they were shown to their sleeping quarters), with becoming arrangement (ie well appointed sleeping quarters).

En hann sjálfr var leiddr í kastala konungsdóttur.
But (And) he himself was lead to (the) castle of the-king’s-daughter (genitive).

Þótti honum þar gott um at sjást. 
(it) seemed to him good to look there-about.

Sæng stóð þar tjölduð með purpura ok guðvef. 
A bed stood there canopied (hung) with costly-purple-stuff and costly-woven-?velvet-cloth

Stólpar allir váru sem á gull sæi, en svá fögr sem sængin var, þá var sú þó enn fegri sem í lá. 
All (bed?)-posts were as-if (one) looks on gold, and as fair as the-bed was, then was that-one (ie she) who lay in (it) yet fairer still.

Því hugði Sigrgarðr gott til sín, ok stígr upp í sængina.
Sigrgarðr thought good in that to himself (thought he was doing well for himself), and steps up (ie climbs) into the-bed.

Jungfrúin var in blíðasta, ok tekr eina gullskál, ok spyrr hvárt hann vill drekka fyrr eðr síðar, en hann biðr hana fyrr drekka. 
The-princess was the most-friendly, and takes one gold-bowl, and asks whether he wants to drink before or later (ie first or second), but (and) he asks her to drink before (ie first).

Hon gjörir svá, en áðr enn hon hafði af drukkit þá hafði Sigrgarðr hallast at hægindum ok var þá svefn á honum, en síðan gengu menn í burt, en þau lágu þar um nóttina. 
She does so, but before she had drunk (it) off, then Sigrgarðr had leaned-over the-pillows and a sleep was then on him (ie he had fallen asleep), but (and) afterwards people (men) (their attendants, presumably) went away, but they (ie the lovers) lay their during the-night.

Ei vaknaði Sigrgarðr fyrr enn jungfrúin var klædd ok í burt gengin. 
Sigrgarðr awoke not before the-princess (lady) was (had) dressed and gone away.

Váru hans menn þar innkomnir ok spurðu hversu honum hefði sofist um nóttina, en hann segist nógu fast sofit hafa. 
His people (men) were (had) come inside there, and asked how (it) had been-slept by him (ie how he had slept) during the night, but (and) he says-of-himself to have slept soundly (lit: fast) enough.

Síðan klæddist hann ok gekk til hallar. 
After-that he dressed-himself and went to (the) hall.

Meykonungrinn var þar fyrir.
The-maiden-king was there before (ie already)

Meykonungrinn tók í hönd Sigrgarði, ok leiddi hann í hásæti ok bað hann vera glaðan. 
The-maiden-king took Sigrgarðr in hand, and led him to (the) high-seat and bade him to be glad.

Síðan settist hon niðr hjá honum ok tóku menn til drykkju, ok var jungfrúin in glaðasta. 
After-that she set-herself down beside him and people (men) took to drink (ie started drinking), and the-princess was the most-glad

Síðan tekr hon eina gullskál. 
After-that she takes one gold-bowl.

Drekkr hon til Sigrgarði ok mælti svá: “Því ertu ei glaðr?” segir hon.
She drinks to Sigrgarðr and spoke thus: “Why (því, Z4) are you not glad?’ says she.

“Frú,” segir hann, “mik uggir at yðr þiki ek litla gleði hafa sýnt yðr á þessi nótt.”
“Madam,” says he, “I fear that (it) seems to you I have shown you little joy on this night.”