SPI flash trouble

Thanks, Gordon. I rebuilt with that, and erased the flash (.eraseAll()) and it seems to work better, but it still seems to choke on larger files (5k or so). A file that works when sent to RAM will throw an error like:

Uncaught ReferenceError: "retur" is not defined
 at line 1 col 1036
...
                              ^
in function "connect" called from line 1 col 410
...
                              ^
in function "GC9A01" called from line 1 col 29
GC9A01(D25, D3, D2, D18, D26);
                            ^
>

as if the keyword "return" were incomplete; but as I said, it IS complete, and works when sent to RAM.
After this point, trying to list files shows an empty list; but if I "reset()", the file list is restored.

It's like it goes to sleep and can't wake up at some point! Insomniac flash.