I have moved new my Desert Rose indoors for the first time due to lower temps, but I don't have a great south-facing window...thoughts, suggestions, help?!? Also, it was outside for a few days that got into the 50's and the leaves are browning on the tips and falling off, is this normal, or even a part of going into dormancy? I love this plant and don't want it to die, please help...

It is okay if it goes into dormancy, they just rest and will wait till the conditions are good again in Spring. In the meantime, scale down watering. This is the time if you overwater you can kill it faster, since it is already showing it is heading to dormancy. As long as the base of the plant and branches are feeling firm to your touch, it is doing okay.