.

src/action.a

@@ -196,6 +196,8 @@ callback_next
          !word kLastPlayed
 .gameptr !word $FDFD                 ; set at runtime
 .loadNewGameInfoAndRepaint
+         lda   #1
+         sta   gNeedToSavePrefs
          jsr   LoadGameInfo
          jmp   RepaintSomeViews
 }

src/prefs.a

@@ -9,6 +9,7 @@
 ;
 ; Public variables
 ; - gCurrentGame          byte       0..kNumberOfGames-1
+; - gNeedToSavePrefs      byte       0=false, 1=true
 ;
 ; Public constants
 ; - kForce40
@@ -24,6 +25,9 @@ kDefaultGame              = 30       ; Zork I
 gCurrentGame
          !byte 0
 
+gNeedToSavePrefs
+         !byte 0
+
 kForce40
          !byte 14
          !raw  "FORCE40COLUMNS"
@@ -47,6 +51,8 @@ kLastPlayed
 ; out:   all registers and flags clobbered
 ;------------------------------------------------------------------------------
 LoadGlobalPreferences
+         stz   gNeedToSavePrefs
+
          jsr   okvs_init
          !word gPrefsStore
 
@@ -146,10 +152,11 @@ LoadGlobalPreferences
 .val     !fill 15
 
 SaveGlobalPreferences
-         lda   #$00
-         sta   $FE
-         sta   .prefslen
-         sta   .prefslen+1
+         lda   gNeedToSavePrefs
+         bne   +
+         rts
++
+         stz   $FE
          lda   #$20
          sta   $FF
 
@@ -207,6 +214,7 @@ SaveGlobalPreferences
          sec
          sbc   #$20
          sta   .prefslen+1
+
          jsr   SaveFile
          !word .globalPrefsFilename
          !byte 4                     ; filetype=TXT
@@ -215,6 +223,8 @@ SaveGlobalPreferences
 .prefslen
          !word $FDFD                 ; set at runtime
          !word kProDOSFileBuffer
+         stz   gNeedToSavePrefs
+
          rts
 
 addBooleanFromStore

src/settingsdialog.a

@@ -195,6 +195,8 @@ callback_options_ok
          jsr   SetPrefByCheckbox
          !byte ID_OPTIONS_AUTOSCRIPT
          !word kAutoScript
+         lda   #1
+         sta   gNeedToSavePrefs
          jsr   SaveGlobalPreferences
                                      ; execution falls through here
 callback_options_cancel