After the girls win the first round of Phoebe's game, Monica and Rachel hug from one angle. Then we see Chandler and Joey's reaction from a different angle and the girls are hugging again.
Given the time that Joey and Chandler are at the basketball game, there's no way the girls could switch and decorate both apartments. Since Phoebe is pregnant, her role in helping would be limited and Rachel does whatever she can in order to get out of doing any type of physical labor. Therefore, Monica would be the only one to move everything.
Rachel and Monica thought they won because Joey and Chandler drew an ace thinking it's the lowest card. Although aces can be used as 1's for straight or straight flushes to 5 in poker, they're usually the highest in other poker hands.
Ross couldn't have had his ear pierced the day before if he is wearing a hoop in his earlobe as earlobe piercings are usually done using a stud earring and have to be in the ear for at least 6 weeks before being changed,therefore he could not have changed to a hoop earring in one day as the piercing would still be healing.
Monica and Rachel have an exchange indicating the bedrooms in the guys' old apartment are so small that Monica (who has Chandler's old bedroom) had to make room by sleeping in a ball on the floor. In numerous other episodes showing Chandler in his bedroom, we see that there is plenty of room for a bed and dresser.