The plot has been summarised as "The quaint village of Byway will be bulldozed to make way for a motorway until alien outcast Kadoyng arrives from Outer Space to help" and doesn't really need any further comment. It's dated badly for an audience today and has some very clunky progress through the plot, but it has some imaginative ideas.
The basic storyline underneath the space age froth reminded me of The Railway Children given a comedy remix, and it has the same affectionate tone. I described the plot summary above on an online forum somewhere else, which got a response wondering if it could have been an influence on Douglas Adams for "The Hitchhiker's Guide to the Galaxy", and there are enough similarities to suggest the link is valid.