video problem

[M.S.]

hi,
http://cage2.republika.pl/pmode_17.tar
Maybe somebody recognises my problem...
This is a set of os independent video macros, which helps drawing:
-points
-lines
-rectangulars

When I write in MAIN.S:
   line   160, 100, 120, 60,  15
is OK, but when I try this:
   line   160, 100, 120, 60,  15
   line   160, 100, 200, 60,  14
is NOT OK.
There are few other problems with drawing bigger number of rectangulars but now it is not so important.
When I emulate it on Bochs it works, in real world it doesn't work. I have heard few voices saying that syntax is good, so I'm asking: What's wrong with this.
Because of this I'm tied coding is assembler.