Getting a graphics LCD subsystem to work can be rather difficult if you miss some simple small details. You should focus your initial work on making small steps such as producing simple code that writes and reads various registers inside the GLCD controller chip. There are many many things that can go wrong at this simple level including errors in schematic, wiring, voltages, fine pitch cables, soldering mistakes etc.

edit: (By simple I mean to look closely at the data sheet for registers that may be read/write and verify that you can at least be successful at writing some bits to various patterns and read then back. This level of verification goes a long long way to eliminating many of the simple mistakes that can thwart a success story.

Build up your confidence in the work you are doing step by step from the simplest to the more complex. Cutting and pasting together code from various web pages and then throwing the whole thing at the display and expecting to immediately see the rectangles is, from my own experience, an awful lot to expect.

Michael Karas