[sacripan]

You cannot just change files like that. There is also a mapname in the header of pwf file, so You need to open the pwf with any hexeditor and change the map also there. If the string's length of the old and new map name is the same - that 100% works. But I cannot say if that helps if the length of the new/old map names is different. I'm not going to support that, anyway (what is the serious reason to change the mapname?). I can give the message the pwf file is corrupted or so in that case.

When you have different length with new/old map names, you rename the map and you change the header of pwf file. Change 00 with letter or letter with 00 but no add. The end of the header name is 00