Your Leaf's CarWings/EV Connect isn't working because the 2015 model has the 2G TCU, which must be replaced with a newer 3G capable unit that will talk to AT&T's cell network (they no longer have 2G). The good news for you is that the upgrade usually costs $199, but for 2015 owners it's supposed to be free. LeafSpy is a diagnostic utility, so not useful for Carwings/EV Connect.
You can try this app, as an alternative (Android): https://play.google.com/store/apps/deta ... ager&hl=en
Having said all that, you mentioned you have an S model (no NAV unit), so Carwings/EV Connect isn't a feature of your car.
With respect to pre-warming the car prior to your commute, you can use the climate control timer. If you have an S model, look at page 4-14 of the owner's manual: https://owners.nissanusa.com/content/te ... manual.pdf
(heading "Climate Ctrl. Timer"). Note that it's much better to use this if you have a level 2 EVSE as it will otherwise drain the battery pack.
With respect to your podcast question, I don't think you can disable the steering wheel controls. However, if you push and HOLD the up/down arrows that should
quickly scan through the MP3. I know that works for radio tuning, just haven't tried it with an MP3 yet...
With respect to range anxiety, it's mostly in your head. After a few weeks with the Leaf, charging just becomes second nature and you'll realize that you rarely need to worry about range. It's really about getting better at thinking ahead and planning your trips more than with an ICE car.
Vancouver, CA owner of a 2013 Ocean Blue SV + QC, purchased 01/2017 in WA
Zencar 12/20/24/30A L1/L2 portable EVSE
1-1/4" Curt #11396 hitch
After market, DIY LED DRLs
LeafSpy Pro + Konnwei KW902 ELM327 BT OBDII dongle
Loving my first BEV