Your Polka Dot Plant (Hypoestes phyllostachya)
is really beautiful!
The few leaves with curled edges don't appear to be the result of the location; a south or west facing window is perfect as long as the plant is not receiving full direct sun on it's foliage. I think the curling leaf issue may be due to lack of humidity. You can raise the humidity by placing the plant on a tray with moist pebbles. Refresh the water as it evaporates to keep the pebbles moist at all times. As the water evaporates, it helps raise the humidity level around plants.
Hopefully others will be along with advice and suggestions soon but you appear to be doing a wonderful job with that beauty!