The various words used in the Qur'an, which may be construed as a description of the face of the earth and which have been referred to by the author of the referred article are: "???", "???", "???", and "??". Besides these words used with reference to the earth, the author has also commented on the use of the word "???" with reference to the sun.
As for the words used with reference to the "shape of the earth", none of these words gives the impression that the earth is not round or spherical. Nevertheless, it would only be honest to submit that neither do these words give the impression that the earth IS round or spherical. In fact, these words are not even related to the "shape" of the earth. On the contrary, all these words are only a reference to the spread, the stretch, the vastness and the spaciousness of the earth.
Each of the four words under consideration is generally explained by the word "???". This point does not need any substantiation, as it is also mentioned (even if partly) by the author of the referred article. However, the word "???" does not imply that the thing being referred to is non-circular or non-spherical. On the contrary, the word has been explained by Lisaan al-Arab as follows:
??? ?????: ????
Bas't al-Shay' implies spreading that thing.
The word does not, in any way, connote a particular shape for the thing in question. It only implies its vastness, stretch, expanse etc. The Qur'an has used the word "???" at a number of instances, and at each one of these instances, the word is used - literally or figuratively - for 'spread', 'expanse', capaciousness etc.
The cited interpretation of Jalalayn is obviously incorrect.
As for the word "???", it is used figuratively for the time when the sun ceases to shine. The word is used in a similar literary style in Al-Zumar 39:5.
Thus, Al-Tabariy has reported that the verse has been interpreted as:
When the sun will cease to shine (when the blaze of the sun is folded away), when it becomes darkened; and
When the sun is overthrown (or thrown away).
According to my understanding, the first of the two stated opinions is correct. Nevertheless, it should be clear that the use of the word "???" has absolutely no connection with the shape of the sun.
I hope this helps.
Regards,
Moiz Amjad