Since you are using XP it is strange that you can not open the chm file. I have no problem opening it in Windows 7. But I am also running XP SP2 in a virtual environment on another machine, I will check the file there also ASAP.
I wonder why you are still using the FS9 version, is it because of the 35OE? There will be a 35OE for FSX in the near future, it is actually already in development.
Awesome avatar by the way! ;)
Win 10 Pro | P3D v5, v4 | AMD Ryzen 3 3.5 GHz | 32 GB RAM | NVIDIA GT1030 | TM HOTAS Warthog | TM HOTAS Cougar