The toilet rocking is from the bolts not being tightened enough. This also has caused the wax seal to separate and not seal. The answer to all your questions are the same. First, go to the hardware store and pick-up a wax seal one with the rubber bottom is better. Also get a new set of T-bolts. Then detach the 5/8" nut on the water line at the back of your toilet. Make sure you flush all the water away first. Then take a pair of vice grips and grab the top of the existing t-bolts or you could also try rocking your toilet in order to creat tension on the bolt. Then try to remove the nuts holding down the toilet. There will either be two or four. If that doesn't work use a hacksaw or angle grinder to cut the old t-bolts off. Then remove the toilet. You should expect to have some water drain from the trap as you remove the toilet so have some towels or rags handy. Try not to tip the toilet too much, this will help reduce the amount of "water" on the floor. Then remove the t-bolts from the toilet flange. They tilt out at the end of the slot they are usually located in. Then install new t-bolts and place the wax seal centered on the flange. Oh yeah, and do try to remember to remove the old wax seal from the flange and toilet. It may not be pleasant but its necessary. Then carefully locate the toilet over the t-bolts and place toilet down seating it on the wax seal. Put some pressure on it. You can sit on it once you have it in the exact place you want it, but be careful to not move it or let it shift or rock. Now tighten the bolts down but do not overtighten because too much pressure will break the base of the toilet... and then it is garbage. Once you have the bolts tightened try out the decorative caps or covers to see if they will fit if not cut down the bolts with a hacksaw be careful not to damage the threads. Then re-attach the water line and you are done.