Hi Radiaoki,
Try this:
Move GMFMODSimple.dll, GSWBINFile.dll, readme.txt, SDL.dll, unins000.dat, unins000.exe, gsw_update_100_1051.exe outside your game folder, leaving only the data folder, gsw.exe, and gsw04_import.exe in the game folder.
Run gsw_update_100_1051.exe, point to the game folder only containing the data folder, gsw.exe, and gsw04_import.exe.
Once update complete (updater should run properly now), move GMFMODSimple.dll, GSWBINFile.dll, readme.txt, SDL.dll, unins000.dat, unins000.exe, gsw_update_100_1051.exe back into the game folder.
Check Game version, verify that it is now version 1051. Run game.
Let me know if this works.