Ok, I think the problem is you're overfermenting the kefir. Upper 20's, lower 30's is pretty warm. The fermentation will go faster the higher the temperature.
Try reducing the amount of time you ferment (as low as 4 hours) or try finding a cooler spot (I realize this may not be practical). If you ferment in a closed container, you should get some light carbonation.
Also it may take a little time for your mother culture to adjust to the new milk source. Sometimes the ferments do funky things for the first few batches when switching to a new source of milk.