I apologize if the multiple posts makes anyone unhappy; I just like having a new post for every update, as it makes it easier for me to track progress and time/dates.
Finished the code (for now) include a Max/Min/Current temp display, using custom characters (the up and down arrows) to identify which is max and which is min, without cluttering the (tiny) display. I ran out of AWG30 wire, so when I pick more up Ill add the LCD to the atmega board and wire it up.

#include <DallasTemperature.h>
#include <LiquidCrystal.h>
// RS EN D4 D5 D6 D7
LiquidCrystal lcd(0, 1, 2, 3, 4, 5);
DallasTemperature tempSensor;
double maxtemp = 0;
double mintemp = 255;
byte up[8] = { 0x04, 0x0E, 0x15, 0x04, 0x04, 0x04, 0x04, 0x00 };
byte down[8] = { 0x04, 0x04, 0x04, 0x04, 0x15, 0x0E, 0x04, 0x00 };
void setup()
{
tempSensor.begin(12);
lcd.begin(16, 2);
lcd.createChar(0, up);
lcd.createChar(1, down);
}
void loop()
{
double temp = tempSensor.getTemperature();
lcd.home();
lcd.write(0);
lcd.setCursor(5,0);
lcd.print(temp);
lcd.write(223);
lcd.print("C");
lcd.setCursor(15,0);
lcd.write(1);
if (temp > maxtemp)
{
maxtemp = temp;
lcd.setCursor(0,1);
lcd.print(maxtemp);
lcd.write(223);
lcd.print("C");
}
if (temp < mintemp)
{
mintemp = temp;
lcd.setCursor(9,1);
lcd.print(mintemp);
lcd.write(223);
lcd.print("C");
}
}