Fifth line
飛龍在天.利見大人.
Daren 大人 (see also line 2) can refer to a person in a high position, like the nobility. In the Shijing 詩經 it is used as the title for a diviner, probably the chief diviner, divining dreams:
下莞上簟、乃安斯寢。
乃寢乃興、乃占我夢。
吉夢維何、維熊維羆、 維虺維蛇。
大人占之。
維熊維羆、男子之祥。
維虺維蛇、女子之祥。
On the rush-mat below, and that of fine bamboos above it,
Here may he repose in slumber!
May he sleep and awake,
[Saying] ‘ Divine for me my dreams.
What dreams are lucky?
They have been of bears and grisly bears;
They have been of cobras and [other] serpents. ‘
The chief diviner will divine them.
The bears and grisly bears,
Are the auspicious intimations of sons.
The cobras and [other] serpents,
Are the auspicious intimations of daughters.
牧人乃夢、眾維魚矣、旐維旟矣。
大人占之、眾維魚矣、實維豐年。
旐維旟矣、室家溱溱。
Your herdsmen shall dream, –
Of multitudes and then of fishes;
Of the tortoise-and-serpent; and then of the falcon banners.
The chief diviner will divine the dreams,
How the multitudes dissolving into fishes,
Betoken plentiful years;
How the tortoise-and-serpent dissolving into the falcon banners,
Betoken the increasing population of the kingdom.
In the Yi the daren might refer to the chief diviner who would perform the bone oracle ritual after the offering has been accepted by the ancestors.
Flying dragon in the sky.
Advantageous to see the chief diviner.
Sixth line
亢龍有悔.
About ‘overconfident’ as a meaning of kang 亢, and hui 悔 as ‘misfortune’ see here. Hui also means ‘regret’ and ‘repent’ because of misfortune caused by your own actions.
An overconfident dragon will have misfortune.
Extra text, ‘Ongoing nines’ (用九)
See a flock of dragons without head.
Auspicious.
on the left side, and 乞 on the right side. This idea would probably be strengthened by the fact that there are more characters with 
.