We add some debug code to your script.
We find not directly an error.

code:

---

?"-    1-"  $rk="HKEY_CURRENT_USER\Network\Persistent"
?"-    2-"  $sknr=0
?"-    3-"  $sk=ENUMKEY("$RK",$sknr)
?"-    4-"  WHILE @error=0
?"-    5-"        $vnr=0
?"-    6-"        $vnm=ENUMVALUE("$RK\$SK",$vnr)
?"-    7-"        WHILE @error=0
?"-    8-"              $vd=READVALUE("$RK\$SK\","$VNM")
?"-    9-"              $vt=READTYPE("$RK\$SK\","$VNM")
?"-   10-"              IF $vnm="RemotePath"
?"-   11-"                    $mnt=$sk+": "+$vd
?"-   12-"                    WRITELINE(1,"| $MNT"+SUBSTR($fill,2+LEN($mnt),78-LEN($mnt))+CHR(13)+CHR(10))
?"-   13-"                    $lc=$lc+1
?"-   14-"              ENDIF
?"-   15-"              $vnr=$vnr+1
?"-   16-"              $vnm=ENUMVALUE("$RK\$SK\",$vnr)
?"-   17-"        LOOP
?"-   18-"        $sknr=$sknr+1
?"-   19-"        $sk=ENUMKEY("$RK",$sknr)
?"-   20-"  LOOP

---

Our script for same duty (it may gives you an idea):

code:

---

    ; - drive-mappings 95 (persistent) -
    $ikey="HKEY_CURRENT_USER\Network\Persistent" ; - 95 -
    $x=""
    $debug_mode="yes"
    IF (existkey($ikey) = 0)
      $completed="no"
      $first=""
      $x=$x+" HKCU.network.persistent[95]=("
      $index=0
      DO
        $icode=ENUMKEY($ikey, $index)
        IF (@error = 0)
          IF ($debug_mode = "yes")
            ? $ikey+"\"+$icode
          ENDIF
          IF (len($icode) <> 0)
            $x=$x+$first+"["+$icode+"=("
            IF (existkey($ikey+"\"+$icode+"\"+"RemotePath") = 0)
              $x=$x+"RemotePath='"    +ReadValue($ikey+"\"+$icode, "RemotePath")+"', "
              $x=$x+"UserName='"      +ReadValue($ikey+"\"+$icode, "UserName")+"', "
              $x=$x+"ConnectionType='"+ReadValue($ikey+"\"+$icode, "ConnectionType")+"'"
            ENDIF
            $first=")],"
            ;
          ENDIF
        ELSE
          $completed="yes"
        ENDIF
        $index=$index+1
      UNTIL ($completed = "yes")
      IF ($first = "")
        $x=$x+")"
      ELSE
        $x=$x+")])"
      ENDIF
      ?
      ? "persistent connection: "+$x

---

Greetings.

BTW: we prepare before reading your reaction.
we will look to the script also.