I was going to recommend going to white flour. You can always convert it back nearly entirely to spelt once it's established, if you want to. I've done that with whole wheat several times.
How long has your starter been culturing? Often around day 3-4 things slow down because the initital bubbles are bateria, not yeast (even though the OJ is supposed to prevent that somewhat). It could also be a heat thing. I like to keep mine in the oven with the light on in the winter, but make sure you keep checking that it's not too warm and burning through food.
Hmmm. About temperature. I've heard it about beer yeast but not bread yeast, and I've heard higher temperatures. (I've also wrapped jars of starter in heating pads to make things move along faster
and they've survived.
) I think most bakers agree 80ish degrees is ideal. But you're right, people have been making bread forever in hot regions, I think these things survive.