PROGMEM with multidimensional Array

Using Arduino Programming Questions
1

I'm running out of dynamic memory and therefore trying to put a multidimensional array of uint8_t values into PROGMEM.
Declared as global const the code runs fine. Pulling back the values from PROGMEM the values are not correct. I get no compile error.
Code that works...

const uint8_t numDotBytes[5][5] =
{{126,129,129,129,126},
{0,130,255,128,0},
{130,193,161,145,142},
{66,129,137,137,118},
{24,20,18,255,16}};
void setup ()
  {
  Serial.begin (115200);
  Serial.println ();
  Serial.print (F("Array Element 3, 0 - 4 "));
  for (int i = 0; i < 5; i++) {
    Serial.print (numDotBytes[3][i]);Serial.print(",");
  }
 } 
void loop() {

}

Code that does not work.

extern const uint8_t numDotBytes[5][5] PROGMEM;
void setup ()
  {
  Serial.begin (115200);
  Serial.println ();
  Serial.print (F("Array Element 3, 0 - 4 "));
  for (int i = 0; i < 5; i++) {
    Serial.print (numDotBytes[3][i]);Serial.print(",");
  }
 }  
void loop() {
}
const uint8_t numDotBytes[5][5] PROGMEM =
{{126,129,129,129,126},
{0,130,255,128,0},
{130,193,161,145,142},
{66,129,137,137,118},
{24,20,18,255,16}};

I'm sure it is something I just don't understand, but have not found a solution in my search.

2

Program memory is not preserved over code writing cycles.

So if those are separate programs, which they are because they each contain a loop function when you load the second one in it will wipe the program memory set up in the first.

3