[Coco] Sailorman and DW ??

[Charlie]

I have a question about something I experienced trying to play Sailor Man using DW and a coco1 on the disk image at this link:

http://sdrv.ms/RytXVL

The file comes from the _games folder in the archice coco1, 2 & 3 games at Tandycoco.com
http://tandycoco.com/dsk_imgs/rs-dos/Games.zip (75mb)

There is a basic program that runs the game called SAILOR.BAS

If you are using a system with a DW rom in a cart, running that program gives you a SN error.

However if I type the important lines manual, they work fine! This is what gets the game going.

LOADM"SAILOR1
EXEC
CLEAR 20,16000
LOADM"SAILOR2
EXEC

Again, if you type that in the game starts fine.

If you make it a program by putting line numbers in front of each command and RUN it, it will get a SN error.
If you loaded DW from disk the DRIVE 0 will start working, and obviously the game wont start.
It goes without saying making the disk image on a real floppy and using it that way works just fine.

So, why can you type these commands and the game will start, but you can't make a program to do the same?

Charlie