04 Vue wont Move after coming to a complete stop when warmed up, if you push it to 10mph it will drive then

Only one code a p1599 engine stall near stall detect. It stalled a few times when it was stuck on ice,
if u stop when it is warmed up it wont launch, but if u stop at the top of a hill and feather the cas as it starts to coast down the hill after it gets to 8-10mph it will drive fine, no shudder, noise or slipping. Once u reach 60mph it rides smoothe, when u push the accelerater down to pass it will pass and show no sing of a trans problem, and if you don't come to a complete stop (don't go any slower then 8mph) it will continue to drive with no sing of problems.
Thanks for your feed back any helps.

Ok thats what I was afraid of, is it possible that the trans is low on cvt fluid. Should I just replace the cover assembly?
Is there any other things that could cause these symptoms, like the tranny cooler or the pressure solenoid.
Thank you for you advice and feed back.

I have also replaced both input/output shaft sensors, when I bought the car the previous owner put regular automatic trans fluid in the trans.
Would doing a complete trans flush help, is it possible that there is still regular automatic trans fluid in the converter that is being circulated thruoght the trans causing inproper fluid velocity and in turn not alowing the trans to reach proper hydraulic pressure (or clamping force) to launch the car.
Thanks you for your feed back

Thank you. Can this type of trans be flushed? I do believe its the VT25E
Is there a special scan tool (the Tec 2 scan tool that GM uses) and special pressure gage needed?
I have an update, after replacing the fluid and filling the trans it seems to be getting better, I have added approximately 9 quarts total to it so far over the past few days, 6-7 after the drain and refil, and about 2, 1/2 quarts (about 1/2quart each day after its warmed up) and it is now launching when its warmed up, I have not been driving it far or putting it under hard driving conditions like it would be subjected too in ever day driving, to try and prevent any more damage.
I would like to know if a flush is possible and if I should have a dealer flush, refil, and put the right additive in, then if I have problems after a bit then test the trans pump and other functions to determine if I should replace parts, rebuild, or junk the car.
Thanks for your feedback

Would you know the part number for the case cover, or the best way to obtain parts for this transmission. Thanks

The auto dealer ran my vin to determine how much fluid I would need, it was very costly, also I followed the fill procedure by adding 4to5 quarts to start with, ran the car and keept adding until the fluid came out the secoundary plug (it made noise like it was low on fluid untill I got all 6 quarts in) I also used the same tool they have at Advace auto to do a snap shot of the engine temp, this tool dosent allow me to control moduels, or read the temp of the trans, just the coolant temp and IAC temp. After this procedure was done it used about 7 quarts untill the fluid ran out the secoundary plug, when I added another 1, 3/4 quarts it started driving fine, before it acted like it was just low on fluid.
I did also flush the cooler lines out by putting rubber houses on one cooler line and the other into a container of fresh fluid and putting compressed air into the container to push fluid into the tube and throught the cooler. Then just air.
The dealer said the use water to flush them and a special adapter they don't have.
I do want to reflush, refill and add the additive to insure it has the proper fluid and level. I would like to find more ligature or info on the refill procedure, once I flush it again I will have the dealer do a pressure check to ensure the trans has proper pressure output Thank you for all your help and detail.

Thank you for responding to my questions, as I said before the dealer said it holds 7.2 quarts, I did put in about 5-6 quarts before the fluid ran out the center of the plug, so in all total over a few days about 8 -9 quarts.
Yesterday I pulled the drain plug and only got about 6 quarts of fluid that drained out, I didnt see any leaks any where and the draind fluid still looked some what contaminated with regular trans fluid, so I am going to flush the cooler and put fresh fluid in it and add the additive, if it still has problems I will have a differnt dealer (not the one that told me to use water) test the pump pressure. Also me scan tool dosent show the trans temp just the coolant and the Intake Air Controls air temp, if the engines coolant is at 178F the intake reads about 76-84F.
Also I did follow the fill procedure you described each time, that is why I was stumped when it was taking over 6 quarts, but as I said the first time I added fluid I only started with 4 quarts and started the car and the trans made noise untill I added 2 more quarts, then about another half a quart untill the fluid ran out the center hole on the drain plug.
I appreciate all your time and feedback you are speding on this subject.

Is there a part number on the side cover, the trans I have is the vt25e (m75).
Is the proper part number 24227081?
I am going to have the pump pressure tested then I will go from there, for now the car will move after warmed up but it is not launching at the proper rpm, once moving it drives fine, whent it is cold it functions properly from a complete stop and all the way up to 80 plus mph but as I said it still doesn't launch properly when at normal operating temp.
Thanks for your feedback.