While running Xojo 2017r3
With HiDPI turned on:
Both macOS/Windows 32-bit and macOS 64-bit gives the same error as above i.e. a NilObjectException error in the Constructor of X3Texture since, while texture exists, it cannot get the Mask property:
But Windows 64-bit gives the Feedback error mentioned below.
With HiDPI turned off:
Runs OK with macOS 32/64-bit
Runs OK with Windows 32-bit
Runs OK with Windows 64-bit the IDE gives a Feedback error Framework failed assertion at runctl.cpp:2260:
So even if I choose to forego HiDPI, I could not produce a Windows 64-bit version of my app.