Really sorry to be a bother again, but now that the installer runs and claims to have installed M4-78EP 1.5, there are no file changes and the mod seems not to be installed. I tried to install Extended Enclave 2.5 afterwards, but the TSLPatcher installer stopped immediately telling me that M4-78 wasn't installed correctly. I've run M478EP 151.exe smoothly several times with no changes to the files. The installation part of the forum post says that it should ask you to indicate the path to the game's folder, but I think it's worth noting that it doesn't give me that option. It extracts all these files for the module folder, override folder and streamvoice folders, but these new files are nowhere to be found.
EDIT - Found that the files do... "exist," but are invisible and inaccessable for some reason. When the installer finishes, it gives me the option to open the Read Me, so I open that just fine. However, it does not come up whatsoever in Windows Explorer except in the "Save As..." window. From this window, I can even right-click the file and go into its Properties. There, the path clearly reads C:\Program Files (x86)\Steam\steamapps\common\Knights of the Old Republic II\M4-78EP Readme.rtf, but disappears without a trace when I try to navigate to it in a new window. I feel like Obi-Wan looking for Kamino right now.