Answer to My BMW Remote app "error during data transfer" issue
I finally figured it out. I was able to use BMW Assist to download Google addresses to my navigation but could not get the functions of the BMW Remote to work (ie: locking, unlocking, horn, etc.). In the BMW Remote app, your login is your email address, just like BMW Assist. You email address for your login must be in ALL CAPS. Simple fix. I went through so many threads and didn't see where anyone had mentioned this. It occurred to me that BMW Assist specifically told me to use all caps for my email address when sending an address to my car. I tried it on the remote app and it worked! Problem solved.