P0700 Chrysler Description The transaxle Control Module (TCM) monitors the malfunction of sensors and actuators relating to transaxle control. When the TCM detects a malfunction with the control, a signal is send to the Engine Control Module (ECM) to trigger the Engine Light or Service Engine Soon light. The ECM stores the P0700 code and it means the TCM detected a malfunction with the transaxle controls.
P0733 gear ratio errors in second and third, these codes set when the input speed is too high for the gear you are in (slipping), or the input speed sensor signal is missing. If the clutch is slipping it could be a seal issue or the accumulators on the valve body. The screws holding the accumulator retainer plate can break and the pistons can come out causing slippage or not moving at all. If the pan was dropped instead of a flush they should have seen this.
It could be one of the speed sensors. There is an input and output speed sensor on the side of the trans. Either one of these can cause this.
P0720 It sounds like you've got a bad output speed sensor. This sensor is threaded into the front of the transmission case all the way on the (vehicle) left of the trans near the side gear cover. It's a white sensor and has a two wire electrical connector. It monitors the output speed of the transmission geartrain and is needed for shifting
P1790 - The harsh downshift comes from an underdrive clutch volume index that is too high, so it's applying the UD clutch too hard at the 2-3 downshift.
This is very commonly just caused by the fluid being low because of a leak. The first thing that needs to be done is check the fluid level with the trans hot, engine idling and trans in park.
If the fluid is full then the problem could be a bad pump in the trans, a leaking low reverse piston or accumulator cover. There is a software update for the trans controller for your exact problem, that would need to be done by a dealer before any internal trans work should be attempted if you don't have any other symptoms.
Whatever the root cause is the harsh downshift can be repaired at least for some time by doing a quicklearn procedure with a scan tool to set the clutch volume indexes back to a baseline to let them relearn correctly. This only takes a few minutes.
P1799 is either a slip in the transmission recorded or transmission fluid temperature too hot