perhaps you will find someone very very very very kind, who reads this thread, who will have pitty and help you
I'll be that someone for you today.
The file (openttd_vs80.vcproj) the conflicting changes are done in is a project file for visual studio (a developing environment some devs and non-devs of openttd use), it includes information like what files belong to the project, in which subfolder (visual studio-internal) they belong, and so on.
If a patch adds a completely new file or removes a file for some reason, it should also contain appropriate changes to openttd_vs80.vcproj, openttd_vs90.vcproj (project files for different versions of visual studio) and source.list (a list of the project files used when not using visual studio - i.e. make). Appropriate here means if a file was added, also add an entry for the file in each of the three files mentioned above, same goes for removing, likewise.
So now if you look at the patch carefully, you'll see that no file is added or removed by it. And look at the changes in openttd_vs80.vcproj carefully: It is only shuffling the entries for some files around. This does not make any sense and you can safely remove those changes from the patch. Not only the shuffling of fiber_win32.cpp, but all and any changes to openttd_vs80.vcproj.
The shuffling around does not change anything in OpenTTD at all; the only difference is if someone uses visual studio, the files will be listed in a slightly different order. And this is also probably the reason why this shuffling was in the patch in the first place - someone (either the patch author or someone who updated it) used visual studio and inadvertedly shuffled the files around (while editing in visual studio), then saved. Then he created the patch and did not notice his (unnecessary) changes done to the project file and now included in the patch.
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I hope that you do not only know now how to fix your problem, but also learned some things that will improve your understanding of the whole thing a bit