Yes, he has explained Purushasukta as well. You can get word-to-word Sanskrit-Hindi translation of Dayanad Sarasvati's Rigveda Bhashya from AryaSamaj, Jamnagar as I've mentioned here. 5th volume contains 9th and 10th Mandala of Rigveda you may read online. English version seems incomplete.
Since you're interested in PurushSukta 90th Sukta of 10th Mandala, you can directly jump to 894th page from where PurushSukta starts and ends at pg. 901. To get the pages you just need to download gif from url
http://www.aryasamajjamnagar.org/rugveda_v5/pages/p894.gif (change page no. accordingly from 894 to 901 before
.gif in the url)
Quoting the Vishesha Vaktavya (special saying) for Purush Sukta:
Translating into English:
This Sukta is known as Purusha Sukta. Purusha=Paramatma, Jivatma and Prakriti are described in this Sukta. The evaluation is not only physical. Prakriti is Purushatmaka. The formation of nice society is not possible without knowing Samsara and it's creation process. That's why Samsara as well as Samaja (society) is described in this Sukta. The description of society is also done by describing Paramatma, Jivatma, forces of Prakriti and the process of creation. The equality/similarity of Sharira (physical body) and Brahmanda
(universe) is also shown.
Read the commentary and translation (page 894-901) to know the explanation by Dayanad Saraswati.