diff --git a/res/dsk/Columns.po b/res/dsk/Columns.po
index d85fbc637..1c49ae655 100644
Binary files a/res/dsk/Columns.po and b/res/dsk/Columns.po differ
diff --git a/src/constants.a b/src/constants.a
index 1ccd478ab..1c7a8675c 100644
--- a/src/constants.a
+++ b/src/constants.a
@@ -19,10 +19,10 @@
 ;
 ; LC RAM BANK 2
 ; D000..D5FF - ProRWTS data
-; D600..D8B6 - ProRWTS code
-; D8B7..DC6F - ProRWTS glue code
-; DC70..DC75 - backup of stack (during gameplay and self-running demos)
-; DC76..DC7B - okvs cache (attract state saved across self-running demo)
+; D600..D8BD - ProRWTS code
+; D8BE..DC76 - ProRWTS glue code
+; DC77..DC7C - backup of stack (during gameplay and self-running demos)
+; DC7D..DC82 - okvs cache (attract state saved across self-running demo)
 ; ...unused...
 ; DFB4..DFFF - (de)acceleration function
 ;
@@ -214,8 +214,8 @@ PRELAUNCH_STANDARD_SIZE = 61         ; LoadStandardPrelaunch, eventually to be d
 ; shared symbols for prelaunch and effects to call ProRWTS2 functions
 iCurBlockLo    = $D601               ; constant
 iCurBlockHi    = $D603               ; constant
-launchpatch    = $D855               ; glue.launch.a
-itraverse      = $DB44               ; Roger Rabbit, avoid, use Infiltrator 2 style instead
+launchpatch    = $D85C               ; glue.launch.a
+itraverse      = $DB4B               ; Roger Rabbit, avoid, use Infiltrator 2 style instead
                                      ; also Columns (via file in disk image)
 ldrlo          = $55                 ; constant
 ldrhi          = $56                 ; constant
diff --git a/src/prorwts2.a b/src/prorwts2.a
index 97c801e27..10405a0e9 100644
--- a/src/prorwts2.a
+++ b/src/prorwts2.a
@@ -521,7 +521,8 @@ slot            ldx     $cfff
                 sta     unrcommand2 + 2
   } ;rwts_mode = 0 and aligned_read = 0 and enable_write = 1
                 sta     unrcommand3 + 2
-                iny      ;STA
+                sta     unrgetreq + 2
+                iny     ;STA
                 sty     unrblokhi1
                 sty     unrunit1 + 2
                 iny     ;STX
@@ -562,13 +563,20 @@ slot            ldx     $cfff
                 sta     unrblokhi2
                 ldy     #$ad ;LDA
                 sty     unrblokhi3
-                iny ;LDX
+                sty     unrgetreq
+                iny     ;LDX
                 sty     unrbloklo2
   } ;rwts_mode = 1 and write_sparse = 1
                 lda     #adrlo
                 sta     unrunit1 + 1
                 lda     #<paddr
                 sta     unrunit1 + 3
+  !if (rwts_mode and write_sparse) = 0 {
+                lda     #$ad ;LDA
+                sta     unrgetreq
+  } ;if rwts_mode = 0 or write_sparse = 0
+                lda     #<pcommand
+                sta     unrgetreq + 1
 
                 ;use SmartPort entrypoint instead
 
@@ -3547,7 +3555,20 @@ pcommand        !byte   $2c ;hide packet in non-SmartPort mode
 unrppacket = unrelochdd + (* - reloc)
                 !word   unrelochdd + (packet - reloc)
 } ;use_smartport = 1
-                bcs     retry
+                bcc     goodread
+unrgetreq = unrelochdd + (* - reloc)
+                lda     reqcmd
+!if use_smartport = 1 {
+                nop ;allow replacing "lda reqcmd" with "lda pcommand" in extended SmartPort mode
+} ;use_smartport = 1
+
+                ;read failures are assumed to be transient
+                ;write failures are assumed to be permanent
+
+                cmp     #cmdread
+                beq     retry
+
+goodread
 !if no_interrupts = 1 {
                 plp
 } ;no_interrupts = 1