Just some thoughts. Also I do not see the Dir command here, as in your post on twitter. I did test dir in a dockerfile on Windows TP5 and it worked fine.
// are not required in the PowerShell execution.
I think that you want to grab the raw gist, they way you had it was pulling the HTML into install.iss.
I do not see the c:\couchbase\server\bin directory, is couchbase.exe supposed to create this?
Just some thoughts. Also I do not see the Dir command here, as in your post on twitter. I did test dir in a dockerfile on Windows TP5 and it worked fine.