[pbiwolski]

Your questions...

Some questions for those who see the soul entering the body at birth: (give references if possible)
1 ) When does the spirit get created? If at conception, why?

I would have to say at conception, although "created" would not be the right word. The scriptures are plenteous in connecting the spirit with our/God's breath and even wind. A few...

Job 27:3 All the while my breath is in me, and the spirit of God is in my nostrils;
Job 33:4 The Spirit of God hath made me, and the breath of the Almighty hath given me life.
Job 34:14 If he set his heart upon man, if he gather unto himself his spirit and his breath;
Ezek. 37:1-14 (spirit likened to wind/breath of God)
John 3:6-8 (spirit likened to wind)

(The "why?" is answered in question 3.)

2 ) If the body is without a soul, is it alive? If no, then when is a baby alive?

Yes, it (the body/flesh) is absolutely alive.

3 ) Does the spirit separate from the soul at any point?

Of course!

Ecc. 12:7 Then shall the dust return to the earth as it was: and the spirit shall return unto God who gave it.
Gen. 49:33 And when Jacob had made an end of commanding his sons, he gathered up his feet into the bed, and yielded up the ghost (spirit), and was gathered unto his people (soul).
Gen. 50:1 And Joseph fell upon his father's face (body), and wept upon him, and kissed him.

The soul does not need the spirit - the body does. As long as the baby is in the mother, it does not need "the spirit" (it's own), it exists off of its mother. Should mom "give up the ghost," there goes the life of the unborn baby.

Job 34:14-15 If he set his heart upon man, if he gather unto himself his spirit and his breath; All flesh shall perish together, and man (the body) shall turn again unto dust.

When the child is conceived, the child receives its own spirit (the breath of life) and becomes a living soul.

4 ) If the pre-born child has no soul, then if death occurs in the womb, does the child cease to exist?

Yes. Please forgive the crude wording, but it is no more that a pile of meat and tissue - flesh. If you allow emotions and humanism to affect your understanding, you'll want to make those harmless unborn babies living in "a better place" (which can nowhere be proven with scripture).
__________________