1)
Why does it say "Karesu Char'u Yachdav"?
1.
Rashi: Refer to 46:1:3:1.
2.
Radak: They crouched to evade being the load, lest the animals carry them.
3.
Malbim: The worshippers of Bel and Nevo, who went to exile carrying their idols, they bowed to them to save them.
2)
What is the meaning of "Lo Yachlu Malet Masa"?
1.
Rashi: They could not excrete the excrement in their hearts innards like those who excrete normally. Malet it is an expression of taking out from where it is enveloped, like "Shamah Kinenah Kipoz va'Temalet" (34:15)
3)
What is the significance of "v'Nafsham ba'Shevi Halachah"?
1.
Radak #1, Malbim: The idols themselves were taken captive
