Heill Daniel!

I looked at your rune-poem translation and it does
have a fair number of inaccuracies. A common error
with the rune poems is to try to read too much into them.
The Icelandic rune 'þula' is really little more than
a collection of kennings and metaphors to describe
a bunch of things. There is little there relevant to,
for example, the magical use of runes.

My suggestion to you for improving your translation is
to use Eysteinn Björnsson's kenning glossary at:

http://www.hi.is/~eybjorn/ugm/kennings/voca.html

There you'll find poetic words that Zoëga doesn't list
- such as 'seiðr' in the sense of "fish".

Kveðja,
Haukur