Let's start with a rough paraphrase of this symbolic and fragmented poem: language is fragmented and persona is fragmented.
Persona lifts self and thoughts to heaven, then falls back down to earth with them (he is attempting poetic thought without inspiration and fails).
Stanza 2 & 3
When inspiration is blocked, it is renewed from nature and the broad cosmos.
Persona finds inspiration and conflict (is not sure what drives conflict).
Persona finds inspiration as do other poets (is not clear what inspires other poets).
Inspiration produces abstraction of involved thought. Poet steps away from real time and place.
The night sky and cosmos pour down inspiration (or rain ...). The torrent of inspiration overwhelms.
Inspiration produces a vast quantity of thought. The demiurge (the creator) is separate from, though part of, the man who is a sleeper.
To interpret this paraphrase to learn what is revealed about Curnow's concept of the creation of poetry, or his aesthetics of poetry, we'll associate it back to the text. Curnow begins on a sleepless night in some tropical clime ["the privets (i.e., evergreen shrub with white blossoms) and the palms"] where his thoughts are devoid of inspiration ("falls behind my house"). He seeks relief out-of-doors with the "washed-out creation" on a night with a bright moon whose light dusts the clouds: "bright clouds dusted (query) by the moon." [This metaphor exchanges sensory elements and has the photons of moonlight dusting material objects, hence the interjection "(query)."]
The poet looks to nature and further, to the cosmos, to find inspiration ("creation"). There he finds two clouds. One represents him and the other an adversary. Is the "adversary" the conflict or paradox of a newly inspired poem or is it the hypothetical intrusion of another poet seeking inspiration?
Inspiration strikes making time seem to stand still so that, lost in abstract thought, temporal association is distorted: "A long moment stretches, the next one is not / on time ...." He is called back to real time by the chilly porch decking. Then, the cosmos floods down a stream of inspiration. The persona, with a recognizable self and a felt inspired poet ("paces me back to bed, stealthily in step"), collects his thoughts and collects his tools for writing and heads back to bed to write.
We conclude that Curnow maintains (1) inspired ideas are difficult to come by; (2) the cosmos (broader than nature) is the inspiration of poets; (3) when inspiration hits, it suspends time as self is lost to the workings of deep abstract contemplation; (4) when reality recalls the mind, a sea of inspired thoughts flood in and must be recorded immediately:
the author, cringing demiurge, who picks up
his litter and his tools and paces me back to bed ....