There was an unfortunate problem with the 64-bit version of the Help Browser which caused it to display an error message when it was loaded. This was due to a module not being linked correctly and has now been fixed.
I have uploaded a refresh release for this (64-bit) platform and you should download and install this over your existing installation - you will not lose any settings by so doing.
Incidentally, the refresh does contain a slightly later (and enhanced) version of the Wallpaper Changer which contains a number of fixes.
Please refer to the download page for the correct link.