Someday I will surely learn the declensions!
Grace
In Jarl átti þessi ríki í Skotlandi, 'þessi ríki' is neut acc plural.
'This kingdom' would be þetta ríki.
In heitir þar Dungalsgnípa er fundurinn var fyrir ofan, 'fyrir ofan' is
'above' not 'below'. See ofan Z4.
Zoega glosses koma e-m í opna skjöldu as 'to take one in the rear'
rather than 'from the side' See opinn Z1
In Snúa þeir Grímur og Helgi þá fram hjá merkinu jarls I suggest that
snúa fram means 'to go or turn forward.' Remember that they have just
been fighting the attackers from the rear and now they are returning to
the frontline, where the earls banner/standard is raised.
In Síðan fór hann norður til Hrosseyjar, 'Horse Island' is genitive
singular. While eyjar is also the nom and acc plural form of ey, the
pronoun til always takes the genitive. Gen sg pl of ey is eyja.
framgöngu from framganga. Z1, advancing, Z2, boldness, courage