- Throw an exception when detecting an out-of-bound read instead of returning random data.
- Catch exception in the parallel read dispatcher, otherwise some destructors that run afterward cause double-exception termination or read invalid memory.

- CrateFile helpers re-throw the exceptions they caught.
- CreateData remembers that exceptions were thrown during I/O and returns an error.
- Cratedata cannot throw an exception because it is invoked in parallel code that crash when exceptions are thrown. Error return are used instead.
- With this, the error propagates to the caller that tried to load the layer or stage.