Well, this is a hella late response, but if you never did find a solution (Or someone else has this problem) here is the probable cause.
Most likely you're missing the allegro5.cfg file.
Open notepad and paste the following into it. Then save it as allegro5.cfg in the same folder as eomap2.exe (or eomap3.exe)
[graphics]
driver=opengl
[opengl_disabled_extensions]
GL_EXT_framebuffer_object=0
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