@Thomas Richard 

Thanks Thomas for your interest.

The file seemed to be uncorrupted.  Also the version you asked about is:

Distributor ID: Ubuntu
Description:    Ubuntu 16.04.3 LTS
Release:        16.04
Codename:       xenial

Best regards and thanks for your interest,

Greg Reid

We did successfully install Maple 18 running under Ubuntu, inWSL thanks to some local help on two Win 10 laptops.

The key steps that appeared to help:

Updating to the most recent release of Win 10 (1803).  We did not succeed with a previous version.  And WSL, a recent product, is still being considerably upgraded.

The second reason seems to be that the licensing manager for Maple, required a window for entering the license code for our versions.  So we installed an X-server, namely Xming, in our case.  We also fetched some additional relevant upgrades for ubuntu, and made some small edits to the .bashrc file.

We are even able to run xmaple, though we only required running scripts and development work on programs in Maple interacting with external numerical homotopy solvers, for general systems of PDE, so we could do so on our personal laptops, and not just on our PCs.

Another possbility suggested to us that we did not pursue, was to mix windows programs and ubuntu programs (since results can be written to a common directory).

Thanks to everyone for their suggestions and interest.

Here I give some additional info showing our failure to install Maple 2018 in ubuntu in WSL under Win 10. 

-bash: ./Maple2018.0LinuxX64Installer.run: cannot execute binary file: Exec format error

See the attached screenshot ...