This is assuming you have Gimp-2.6.11 installed and you have installed the latest help files into it.

Setting up help for Gimp-2.7 (Parthas Portable)
Download the files for help browser that MareroQ provided.

You need these dll files from Gimp-2.6.11 bin folder.Copy them to the Gimp-2.7/bin folder.
libxml2.dll
iconv.dll

Copy the entire help folder from gimp-2.0/share/gimp/2.0/ folder to the Gimp-2.7/share/gimp/2.0 folder

THE DOWNLOADED ZIP FILE
Copy the libgtkhtml-2.0.dll to the Gimp-2.7/bin folder.
Copy the help.exe file to your gimp-2.7.4/.gimp-2.7/plug-ins folder (this is the USER add on resources plug-ins folder)

Restart Gimp-2.7 (i used Parthas portable version)
Go to Edit>Preferences>Help System, and set it up as i shown in the earlier post.

Everything should already be set for you as Gimp will recognize it has the files.
Go to Help>Help and there you go.

and for 64 bit ?
any idea ?

for the 32 bit is also needed libxml2.dll.
i suppose may be fixed recompiling the help browser because in 2.7 there is a newer version of the same .dll (libxml2-2.dll )
but anyway the plugin as compiled now need the older version of the dll to work

DONE !

To make life easier to others i repacked everything (last English Help files, + the plugin browser with all its dependencies and a HOW_TO_INSTALL.txt file) in zip and 7zip (same content, smaller file size).

Uploading now i will open a new topic with the links

Thanks PC.