I have two 'tense' questions: 1) when 'ta pral' is written together does it mean "maybe or might"? and 2) under what circumstances does 'ap' come between the verbs as in komanse ap vole?

t'a pral (contracted) → te ap pral (uncontracted) → indicates a past action that intended to happen in the future.
Examples:
Mwen t'a pral manje, ...
I was going to eat, ...

Nou t'a pral soti, ...
We were going to go out, ...

Li t'a pral kite madanm li, men madanm li te tonbe malad.
He was going to leave his wife, but she fell ill.

Maybe or might sentences are made with ka, kab, or kapab
Check out this post on MAY and MIGHT

"Under what circumstances does 'ap' come between the verbs as in komanse ap vole?"

This happens when the first verb 'acts' as a helping verb, and the second verb (which becomes the main verb) is in a progressive or infinitive form.  The main verb would indicate a continuing action occurring for the length of time indicated in the sentence.

Li kòmanse ap vole.

It started flying.

It started to fly.

Li te kontinye ap kriye.

She continued crying.

She continued to cry.

Li plede ap pale.

She kept on talking.

Lè timoun yo te tonbe dòmi, li te koumanse ap ranmase jwèt yo atè a.

When the kids fell asleep, she started picking up the toys off the floor.

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