diff --git a/Cart_Reader/Cart_Reader.ino b/Cart_Reader/Cart_Reader.ino
index c0c62f9..a672655 100644
--- a/Cart_Reader/Cart_Reader.ino
+++ b/Cart_Reader/Cart_Reader.ino
@@ -830,7 +830,7 @@ boolean checkCartSelection(FsFile& database, void (*readData)(FsFile&, void*), v
     print_STR(press_to_select_STR, 1);
 #elif defined(SERIAL_MONITOR)
     println_Msg(F("U/D to Change"));
-    println_Msg(F("Space to Select"));
+    println_Msg(F("Space/Zero to Select"));
 #endif
     display_Update();
 
@@ -905,7 +905,7 @@ void printInstructions() {
     print_STR(press_to_select_STR, 1);
 #   elif defined(SERIAL_MONITOR)
     println_Msg(F("U/D to Change"));
-    println_Msg(F("Space to Select"));
+    println_Msg(F("Space/Zero to Select"));
 #   endif /* ENABLE_OLED | ENABLE_LCD | SERIAL_MONITOR */
 
     display_Update();
@@ -980,6 +980,15 @@ int navigateMenu(int min, int max, void (*printSelection)(int)) {
     }
   }
 }
+#elif defined(SERIAL_MONITOR)
+int navigateMenu(__attribute__((unused)) int min,__attribute__((unused)) int max, void (*printSelection)(int)) {
+    printSelection(0);
+    Serial.println(F("Enter number to change:_"));
+    while (Serial.available() == 0) {}
+    int selectedNumber = Serial.parseInt();
+    delay(200);
+    return selectedNumber;
+}
 #   endif /* (ENABLE_OLED | ENABLE_LCD) */
 # endif /* ENABLE_<CORES> */
 
@@ -2844,18 +2853,24 @@ void blinkLED() {
 #if defined(ENABLE_VSELECT)
   // Nothing
 #elif defined(HW5)
+  // 3mm LED on D38, front of PCB
   PORTD ^= (1 << 7);
 #elif defined(ENABLE_OLED)
+  // 5mm LED on D10, above SD slot
   PORTB ^= (1 << 4);
-#elif defined(ENABLE_LCD)
+#elif defined(ENABLE_LCD) // HW4 
+  // TX LED on D1, build-in
   PORTE ^= (1 << 1);
 #elif defined(ENABLE_SERIAL)
-  PORTB ^= (1 << 4);
+  // 5mm LED on D10, above SD slot (HW3)
+  PORTB ^= (1 << 4); //HW4/HW5 LCD RST connects there now too
+  // 3mm LED on D38, front of PCB (HW5)
   PORTB ^= (1 << 7);
 #endif
 }
 
 #if defined(HW5) && !defined(ENABLE_VSELECT)
+// 3mm LED on D38, front of PCB
 void statusLED(boolean on) {
   if (!on)
     PORTD |= (1 << 7);
@@ -3159,7 +3174,7 @@ uint8_t checkButton() {
   }
 
   //Selection
-  else if (incomingByte == 240) {
+  else if ((incomingByte == 240) || (incomingByte == -16) || (incomingByte == 0)) {
     return 3;
   }
 
diff --git a/Cart_Reader/GBA.ino b/Cart_Reader/GBA.ino
index ef4336a..171c56a 100644
--- a/Cart_Reader/GBA.ino
+++ b/Cart_Reader/GBA.ino
@@ -2532,7 +2532,9 @@ byte selectBlockNumber(boolean option) {
     blockNumber = navigateMenu(0, 63, &printblockNumber);
   else
     blockNumber = navigateMenu(0, 32, &printFileSize);
+#if (defined(ENABLE_OLED) || defined(ENABLE_LCD))
   display.setCursor(0, 56);  // Display selection at bottom
+#endif
   if (option) {
     print_Msg(F("Block Number: "));
     println_Msg(blockNumber);
@@ -2569,6 +2571,9 @@ void read369in1(byte blockNumber, byte fileSizeByte) {
   unsigned long lastBlock = 0x2000000;
   if (fileSize < lastBlock)
     lastBlock = startBlock + fileSize;
+  unsigned long lastBuffer = 0x400000;
+  if (fileSize < lastBuffer)
+    lastBuffer = fileSize;
 
   //Initialize progress bar
   uint32_t processedProgressBar = 0;
@@ -2582,7 +2587,7 @@ void read369in1(byte blockNumber, byte fileSizeByte) {
       // Set-up 369-in-1 mapper
       mapBlock369in1((currBank + currBlock) / 1024 / 1024);
       // 4MB Block
-      for (unsigned long currBuffer = 0; currBuffer < 0x400000; currBuffer += 1024) {
+      for (unsigned long currBuffer = 0; currBuffer < lastBuffer; currBuffer += 1024) {
         // 1024 byte readBuffer
         for (int currWord = 0; currWord < 1024; currWord += 2) {
           word tempWord = readWord_GBA(currBlock + currBuffer + currWord);
@@ -2723,9 +2728,9 @@ void write369in1(byte blockNumber) {
 void flashRepro_GBA(boolean option) {
   // Check flashrom ID's
   idFlashrom_GBA();
-  byte blockNum;
 
   if ((flashid == 0x8802) || (flashid == 0x8816) || (flashid == 0x227E) || (flashid == 0x8812)) {
+    byte blockNum = 0;
     print_Msg(F("ID: "));
     print_Msg(flashid_str);
     print_Msg(F(" Size: "));
diff --git a/Cart_Reader/MD.ino b/Cart_Reader/MD.ino
index 4bed801..ef8ed58 100644
--- a/Cart_Reader/MD.ino
+++ b/Cart_Reader/MD.ino
@@ -2896,7 +2896,9 @@ void printRomSize_MD(int index) {
 void force_cartSize_MD() {
   cartSize = navigateMenu(0, 9, &printRomSize_MD);
   cartSize = pgm_read_byte(&(MDSize[cartSize])) * 131072;
+  #if (defined(ENABLE_OLED) || defined(ENABLE_LCD))
   display.setCursor(0, 56);  // Display selection at bottom
+  #endif
   print_Msg(FS(FSTRING_ROM_SIZE));
   print_Msg(cartSize / 131072);
   println_Msg(F(" Mbit"));
diff --git a/Cart_Reader/NES.ino b/Cart_Reader/NES.ino
index 2b1241d..089000e 100644
--- a/Cart_Reader/NES.ino
+++ b/Cart_Reader/NES.ino
@@ -1163,7 +1163,7 @@ setmapper:
   String newmap;
   bool mapfound = false;
   Serial.println(F("SUPPORTED MAPPERS:"));
-  for (size_t i = 0; i < mapcount; i++) {
+  for (int i = 0; i < mapcount; i++) {
     mapselect = pgm_read_word(mapsize + i);
     Serial.print("[");
     Serial.print(mapselect);
@@ -1257,7 +1257,7 @@ void setPRGSize() {
   else {
 setprg:
     String sizePRG;
-    for (size_t i = 0; i < (prghi - prglo + 1); i++) {
+    for (int i = 0; i < (prghi - prglo + 1); i++) {
       Serial.print(F("Select PRG Size:  "));
       Serial.print(i);
       Serial.print(F(" = "));
@@ -1325,7 +1325,7 @@ void setCHRSize() {
   else {
 setchr:
     String sizeCHR;
-    for (size_t i = 0; i < (chrhi - chrlo + 1); i++) {
+    for (int i = 0; i < (chrhi - chrlo + 1); i++) {
       Serial.print(F("Select CHR Size:  "));
       Serial.print(i);
       Serial.print(F(" = "));
@@ -1435,7 +1435,7 @@ void setRAMSize() {
   else {
 setram:
     String sizeRAM;
-    for (size_t i = 0; i < (ramhi - ramlo + 1); i++) {
+    for (int i = 0; i < (ramhi - ramlo + 1); i++) {
       Serial.print(F("Select RAM Size:  "));
       Serial.print(i);
       Serial.print(F(" = "));