diff --git a/README.md b/README.md
index 5c4767a..ae96c9f 100644
--- a/README.md
+++ b/README.md
@@ -43,7 +43,7 @@ Ensure you have your latest graphics card drivers installed before use.
 | UTF-8 output                | ✔    | Works as long as the font in use supports the relevant characters.
 | Copy/paste                  |      | Paste working, no mouse interaction for copy
 | Customisable colour schemes | ✔    | Complete, but the config file has no entry for this yet 
-| Config file                 |      | Minimal options atm
+| Config file                 | ✔    | Minimal options atm
 | Scrolling                   |      | Infinite buffer implemented, need GUI scrollbar & render updates
 | Mouse interaction           |      | 
 | Sweet render effects        |      | 
@@ -63,9 +63,17 @@ The following options are available:
 |---------------|---------|---------|-----------------------|
 | debug         | bool    | False   | Enables debug logging 
 
+
+## Flags
+
+| Name            | Type    | Default |Description            |
+|-----------------|---------|---------|-----------------------|
+| --debug         | bool    | False   | Enables debug logging |
+| --ignore-config | bool    | False   | Ignores user config files and uses defaults
+
 ## Keyboard Shortcuts
 
 | Operation | Key(s)              |
 |-----------|---------------------|
 | Paste     | ctrl + alt + v
-|||
+
diff --git a/gui/cell.go b/gui/cell.go
index b5bdef5..58c3843 100644
--- a/gui/cell.go
+++ b/gui/cell.go
@@ -13,8 +13,10 @@ type Cell struct {
 	cv         uint32
 	colourAttr uint32
 	points     []float32
-	colour     [3]float32
+	bgColour   [3]float32
+	fgColour   [3]float32
 	hidden     bool
+	r          rune
 }
 
 func (gui *GUI) NewCell(font *v41.Font, x float32, y float32, w float32, h float32, colourAttr uint32, bgColour [3]float32) Cell {
@@ -23,7 +25,7 @@ func (gui *GUI) NewCell(font *v41.Font, x float32, y float32, w float32, h float
 		colourAttr: colourAttr,
 	}
 
-	cell.colour = bgColour
+	cell.bgColour = bgColour
 	cell.text.SetPosition(mgl32.Vec2{x, y})
 
 	x = (x - (w / 2)) / (float32(gui.width) / 2)
@@ -45,19 +47,34 @@ func (gui *GUI) NewCell(font *v41.Font, x float32, y float32, w float32, h float
 
 }
 
-func (cell *Cell) SetFgColour(r, g, b float32) {
+func (cell *Cell) SetRune(r rune) {
+	if cell.r == r {
+		return
+	}
 	if cell.text != nil {
+		if r == '%' {
+			cell.text.SetString("%%")
+		} else {
+			cell.text.SetString(string(r))
+		}
+	}
+	cell.r = r
+}
+
+func (cell *Cell) SetFgColour(r, g, b float32) {
+	if cell.text != nil && (cell.fgColour[0] != r || cell.fgColour[1] != g || cell.fgColour[2] != b) {
+		cell.fgColour = [3]float32{r, g, b}
 		cell.text.SetColor(mgl32.Vec3{r, g, b})
 	}
 }
 
 func (cell *Cell) SetBgColour(r float32, g float32, b float32) {
 
-	if cell.colour[0] == r && cell.colour[1] == g && cell.colour[2] == b {
+	if cell.bgColour[0] == r && cell.bgColour[1] == g && cell.bgColour[2] == b {
 		return
 	}
 
-	cell.colour = [3]float32{r, g, b}
+	cell.bgColour = [3]float32{r, g, b}
 	cell.Clean()
 	cell.makeVao()
 }
@@ -83,12 +100,12 @@ func (cell *Cell) makeVao() {
 	gl.GenBuffers(1, &cell.cv)
 	gl.BindBuffer(gl.ARRAY_BUFFER, cell.cv)
 	triColor := []float32{
-		cell.colour[0], cell.colour[1], cell.colour[2],
-		cell.colour[0], cell.colour[1], cell.colour[2],
-		cell.colour[0], cell.colour[1], cell.colour[2],
-		cell.colour[0], cell.colour[1], cell.colour[2],
-		cell.colour[0], cell.colour[1], cell.colour[2],
-		cell.colour[0], cell.colour[1], cell.colour[2],
+		cell.bgColour[0], cell.bgColour[1], cell.bgColour[2],
+		cell.bgColour[0], cell.bgColour[1], cell.bgColour[2],
+		cell.bgColour[0], cell.bgColour[1], cell.bgColour[2],
+		cell.bgColour[0], cell.bgColour[1], cell.bgColour[2],
+		cell.bgColour[0], cell.bgColour[1], cell.bgColour[2],
+		cell.bgColour[0], cell.bgColour[1], cell.bgColour[2],
 	}
 	gl.BufferData(gl.ARRAY_BUFFER, len(triColor)*4, gl.Ptr(triColor), gl.STATIC_DRAW)
 	gl.EnableVertexAttribArray(cell.colourAttr)
@@ -124,17 +141,6 @@ func (cell *Cell) Hide() {
 	cell.hidden = true
 }
 
-func (cell *Cell) SetRune(r rune) {
-	if cell.text != nil {
-		if r == '%' {
-			cell.text.SetString("%%")
-		} else {
-			cell.text.SetString(string(r))
-		}
-
-	}
-}
-
 func (cell *Cell) Release() {
 	if cell.text != nil {
 		cell.text.Release()
diff --git a/main.go b/main.go
index 490a1bf..3dfbdfd 100644
--- a/main.go
+++ b/main.go
@@ -1,6 +1,7 @@
 package main
 
 import (
+	"flag"
 	"fmt"
 	"io/ioutil"
 	"os"
@@ -12,7 +13,19 @@ import (
 	"go.uber.org/zap"
 )
 
-func loadConfig() config.Config {
+func getConfig() config.Config {
+	ignore := false
+	flag.BoolVar(&ignore, "ignore-config", ignore, "Ignore user config files and use defauls")
+	if ignore {
+		return config.DefaultConfig
+	}
+	conf := loadConfigFile()
+	flag.BoolVar(&conf.DebugMode, "debug", conf.DebugMode, "Enable debug logging")
+	flag.Parse()
+	return conf
+}
+
+func loadConfigFile() config.Config {
 
 	home := os.Getenv("HOME")
 	if home == "" {
@@ -56,7 +69,7 @@ func getLogger(conf config.Config) (*zap.SugaredLogger, error) {
 func main() {
 
 	// parse this
-	conf := loadConfig()
+	conf := getConfig()
 
 	logger, err := getLogger(conf)
 	if err != nil {
diff --git a/terminal/escapes.go b/terminal/escapes.go
index 8a70d02..5779b2b 100644
--- a/terminal/escapes.go
+++ b/terminal/escapes.go
@@ -394,9 +394,9 @@ func (terminal *Terminal) processInput(buffer chan rune) {
 				default:
 					terminal.logger.Errorf("Unknown OSC control sequence: 0x%02X", b)
 				}
-			case rune('c'):
+			case 'c':
 				terminal.logger.Errorf("RIS not yet supported")
-			case rune(')'), rune('('):
+			case ')', '(':
 				b = <-buffer
 				// todo charset changes
 				//terminal.logger.Debugf("Ignoring character set control code )%s", string(b))
@@ -424,12 +424,19 @@ func (terminal *Terminal) processInput(buffer chan rune) {
 			case 0x08:
 				// backspace
 				terminal.position.Col--
+				if terminal.position.Col < 0 {
+					terminal.position.Col = 0
+				}
 			case 0x07:
 				// @todo ring bell
 			default:
 				// render character at current location
 				//		fmt.Printf("%s\n", string([]byte{b}))
-				terminal.writeRune(b)
+				if b >= 0x20 {
+					terminal.writeRune(b)
+				} else {
+					terminal.logger.Error("Non-readable rune received: 0x%X", b)
+				}
 			}
 
 		}
diff --git a/terminal/terminal.go b/terminal/terminal.go
index 9daa80e..4bf6fa8 100644
--- a/terminal/terminal.go
+++ b/terminal/terminal.go
@@ -179,7 +179,7 @@ func (terminal *Terminal) getBufferedLine(line int) *Line {
 		line = len(terminal.lines) - int(terminal.size.Height) + line
 	}
 
-	if line >= len(terminal.lines) {
+	if line < 0 || line >= len(terminal.lines) {
 		return nil
 	}
 
@@ -328,6 +328,9 @@ func (terminal *Terminal) SetSize(newCols int, newLines int) error {
 				terminal.position.Line = len(terminal.lines) - 1
 			}
 		}
+		if terminal.position.Line < 0 {
+			terminal.position.Line = 0
+		}
 
 	}