FWIW, the chip I ran that simple example on was rev A2 silicon.

Code:
   FLASH1_CE     con 19'= LATC.3  ' Chip select FLASH chip ( low) 
   LATA.0[FLASH1_CE] = 1      ' Active Low so set High to start
This isn't your problem here, but I'd be careful using that syntax to access a bit in LATC.
I've seen chips where the LATx (and other port related regs) aren't contiguous in memory so that would fail.