Program received signal SIGSEGV, Segmentation fault.
num_rooms_avail (ch=0x5180000d8080) at mapout.c:412
412        for( i = ch->pcdata->area->low_r_vnum; i <= ch->pcdata->area->hi_r_vnum; i++ )
(gdb) print ch
$1 = (CHAR_DATA *) 0x5180000d8080
(gdb) print ch->pcdata
$2 = (PC_DATA *) 0x51b00000ee80
(gdb) print ch->pcdata->area
$3 = (AREA_DATA *) 0x0

Naturally not a big deal comes from not having an area assigned and using mapout write and then mapout stat.

<49hp 145m 110mv> <#200> mapout create
Couldn't give you a map object.  Need Great Eastern Desert

Might want to toss in a map object for it too.

in mapout.c around line 499 find

      switch ( c )
      {
         case '\n':
            break;
         case '\r':
            col = 0;
            row++;
            break;
      }

change it to

      switch ( c )
      {
         case '\n':
            row++;
            col = 0;
            break;

         case '\r':
            col = 0;
            row++;
            break;
      }

This will allow it to create and link the rooms correctly.
Mapout code supports sectors that map_exits doesn't like and gives bug messages about.

The code is also missing support for SECT_ICE, which was added at some point during development.

In mapout.c, find:

         else if( code == 'L' )
            location->sector_type = SECT_LAVA;
         else if( code == 'W' )
            location->sector_type = SECT_SWAMP;

Below that, add:

         else if( code == 'i' )
            location->sector_type = SECT_ICE;

Lowercase "i" should work well enough here since uppercase "I" is already taken.