The version of DOS4GW.EXE typically provided with the original games has long been superceeded with a newer, less buggy, more efficient version 2.01a, but that version is not free-as-in-freedom-or-beer. Tenberry also makes a "high-performance" "pro" version of DOS4G, but it costs $300.
There is a free-as-in-beer-and-in-freedom alternative at http://dos32a.narechk.net/index_en.html. It is a drop-in replacement for DOS4GW.EXE, but is much faster and more efficient. All you need to do is rename the Linux binary "DOS4GW.EXE" and replace the orginal DOS4GW.EXE.
It can be easily scripted to download, re-name and become the replacement. I ahve found it to be a useful and noticably better replacement for DOS4GW.EX.