use kGlobalPrefsBuffer for writing data stored at kGlobalPrefsBuffer, because otherwise things go poorly

src/glue.prorwts2.lc2.a

@@ -69,7 +69,7 @@ SaveSmallFileInternal
          ;jsr   hddopendir            ; call ProRWTS2         
          ;lda   ldrlo2
          sta   ldrlo
-         lda   #$80 ;lda   ldrhi2
+         lda   #>kGlobalPrefsBuffer ;lda   ldrhi2
          sta   ldrhi
          lda   #cmdwrite             ; write (instead of read)
          sta   reqcmd

src/parse.prefs.a

@@ -15,7 +15,7 @@
 ; - kCheat
 ;
 
-kGlobalPrefsBuffer = $BD00
+kGlobalPrefsBuffer = $BD00           ; [512 bytes] must be page-aligned
 
 ; valid pref keys
 kNextAttract
@@ -217,13 +217,13 @@ pref_set
 
          +LDADDR kGlobalPrefsFilename ; write prefs buffer to file on disk
          jsr   SetPath
-;;         +LDADDR kGlobalPrefsBuffer
          ; /!\ execution falls through here to glue.prorwts/SaveSmallFile
 ;------------------------------------------------------------------------------
 ; SaveSmallFile
 ; Save a file into memory all at once, using ProRWTS2.
 ; /!\ Only first block (512 bytes) is written. Keep those files small. /!\
 ; /!\ All 512 bytes are written to disk. Clear buffer before calling. /!\
+; /!\ Address is hardcoded to kGlobalPrefsBuffer /!\
 ;
 ; supports paths, see note
 ;
@@ -233,7 +233,6 @@ pref_set
 ;        all registers clobbered
 ;------------------------------------------------------------------------------
 SaveSmallFile
-;;         +ST16 ldrlo                 ; set data buffer address for ProRWTS2
          jsr   SwitchToBank2
          jsr   SaveSmallFileInternal
          jmp   SwitchToBank1