k, 175.
Code:

Function m($_)

 dim $,$b,$c

 for $b = 1 to 15
  $c = split("- . : .: :: | " + $)
  $ = $ + $c[$b] + "| "
 next

 for each $ in split($_)
  $m = $m * 20 + ascan($c,$)
  if $m<0
   $m = $c[$_ mod 20]
   $ = $_/20
   if $
    $m = m($) + " " + $m
 
EndFunction

Code:

Mayan Number Converter passed all 60 tests (100% correct)

KiXtart
KiXtart Version  = 4.52 Release Candidate 1
KiXGolf Script   = kixgolf_mnc.kix

Computer
OS               = Windows XP Professional
CPU              = Intel Pentium Model 13
Speed            = 1866 MHz
Memory           = 760 MB

KiXGolf Scoring Engine
Scoring Engine   = 3.0.3

KiXtart Golf Score
Tournament       = KiXtart Golf: Mayan Number Converter
Processing Start = 2006/07/24 18:52:45.171
Processing End   = 2006/07/24 18:52:45.359
Duration         = 0000/00/00 00:00:00.187
KiXGolf Score    = 175