height and tile textures are both integers.
DIM map(100,100,2) `x,z,height and texture
Make Matrix matrixID,1000,1000,100,100
`other matrix stuff
update matrix (matrixID)
REM put information into the DIM
FOR StoreX = 0 to 99
FOR StoreZ = 0 to 99
map(StoreX,StoreZ,0) = get matrix height(matrixID,StoreX,StoreZ)
map(StoreX,StoreZ,1) = whatever that tiles texture ID is
NEXT StoreZ
NEXT StoreX
REM Save the DIM to file
If File Exist("themap.abc") = 0 then Make File "themap.abc"
Open File "themap.abc", filenumber
SAVE ARRAY filenumber, Map(100,100,2)
Close File filenumber
REM Load the DIM from file
If File Exists "themap.abc") = 1
Open File "themap.abc", filenumber
LOAD ARRAY filenumber, Map(100,100,2)
Close File filenumber
ELSE
text 0,0,"map file does not exist"
ENDIF
REM apply the DIM to the matrix
FOR LoadX = 0 to 99
FOR LoadZ = 0 to 99
set matrix height(matrixid,LoadX,LoadZ,map(LoadX,LoadZ,0))
set matrix tile/texture/whatever,map(LoadX,LoadZ,1)
NEXT LoadZ
NEXT LoadX
update matrix (matrixID)
If I had my editor I'd give you exact commands and code, but that's the general idea. A quick search should find all the correct syntax for you.
http://ausukusa.breakset.com