Due to the many question, merely read the following: Adapted from talemul haqq (basic book for basic everyday rules with minor editing from our side for the purposes of clarity)

Things Makrooh (disliked actions) while fasting

1. To chew gum, rubber, plastic items or other such things.
2. To taste any article of food or drink and spit it out. If a woman has a very ill-tempered husband, it is permissible for her to taste the food provided it does NOT go down the throat.
3. To collect one’s saliva in the mouth and then to swallow it trying to quench thirst.
4. To delay a bath that has become FARZ knowingly until after Subha Sadiq (the break of dawn).
5. To use paste or tooth powder to clean one’s teeth. It is permitted to clean with a miswaak of any fresh branch or (tooth stick).
6. To complain of hunger and thirst.
7. To take the water too much up the nostrils when cleaning the nose.
8. To gargle more than necessary.
9. To quarrel, argue, use filthy or indecent words.
10. To backbite, tell a lie and swear etc. are sinful acts even when one is not fasting. Therefore they become even worse when fasting.

May Allah (SWT) bless the author(s)