Thanks.
About an hour after I posted, I gave up on my Tier 1 WIP and started converting it to Tier 2.
In iOS/Android, it was experiencing randomish delete errors. The Xcode interface would say that I was trying to unallocate a pointer that had not been allocated. 90% of the time it was for a string, the rest for for a sprite.
I went through the code that it was dying in and there is nowhere that I am deleting a sprite that I hadn't explicitly created. The rest were using static strings in function calls.
I finally decided, after doing lots of things to 'fix' the string issue, that I couldn't be bothered with this type of error anymore.
I'm converting my app to Tier 1 where I have better control and a decent debugger.
But it is good to know that what I suspected about Tier 1 is correct.
Cheers,
Ancient Lady
AGK Community Tester