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Please see the official X‑Plane Support page for help.
Since posting and with some clues from the respondents I have got it installed. The secret is not to run the install program as you download but to save it into a "Free" area of a HDD. Then run/unzip from that location to where you want it installed.
I think the instructions on the X-Plane site could reflect this for the average guy/girl.
The log attached to the original question was an X-Plane 10 installer.
If you want to install the demo of X-Plane 10 (which has a 32 bit version) use the installer here.
If you want to install X-Plane 11, the installer is located here. Please use these instructions to install X-Plane with the correct installer.
Please always include a copy of either the installer log.txt (found on the desktop after using the installer) or the log.txt from the main X-Plane folder if you are using the simulator.
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