Ok guys, I was able to replicate the problem. Luckily I have an IPad for my son that I was able to test with. I had to completely delete the ABC app and start over.
It looks like if you are setting up the App for the first time on an IOS device (android works fine) it locks up as described. I don’t believe this happened before the recent smartthings app update.
It only seems to happen the very first time you try to create a new mapping directly after installing the smartApp. After the initial lock up everything runs fine for me.
I will dig into this and hopefully it’s something simple.