really preserve swap during initial header load

src/4live.a

@@ -80,8 +80,7 @@
         WIDTH           = 40
         HEIGHT          = 24
         LDRBASE         = $2DB
-        INSTALLBUFFER   = $21E          ; yes, the overlay overwrites the loader...
-                                        ; see also "warning!" below
+        INSTALLBUFFER   = $20E          ; yes, the overlay overwrites the loader...
         SWAPBUFFER      = $900          ; (LoadSaveEnd - LoadSaveStart) size
                                         ; needed by Diversi-DOS, must be page-aligned
                                         ; region is preserved across calls
@@ -362,6 +361,10 @@ InstallStart
 +
         ;open source file and read header if available
 
+        lda     SWAPBUFFER
+        pha
+        lda     SWAPBUFFER+1
+        pha
         jsr     LoadSaveHeader
         bcs     +
         lda     SaveCH
@@ -375,6 +378,10 @@ InstallStart
         dec     PreventAddPage + 1      ;tri-state flag because Diversi-DOS
         inc     HeaderExists + 1
 +
+        pla
+        sta     SWAPBUFFER+1
+        pla
+        sta     SWAPBUFFER
 
         jsr     SetTextCoords1
 
@@ -1694,7 +1701,7 @@ SecondLine
         !fill   WIDTH * 7, SPACE
         !text   "         4LIVE by 4am && qkumba         "
         !fill   WIDTH, SPACE
-        !text   "   Revision 05 / Serial number 180410   "
+        !text   "   Revision 06 / Serial number 190318   "
         !fill   WIDTH * 2, SPACE
         !text   "    https://github.com/a2-4am/4live     "
         !fill   WIDTH * 9, SPACE