customizing an info window with geolocation views
Having clarified this with the developer, you need to alter the  ip_geoloc_gmap_multi_loc.js file at line
165.  This relates to the infoWindow maxWidth setting.  Essentially I have
tried to increase this massively.  

This sorts out the problem for me, and the developer advised me that this should not cause a problem.  

I couldn't work out how to do this with css.  Might be possible...but I couldn't work it out...

...hope this helps someone in the future, as it caused me quite a headache!

Thanks again for your posts,

Mark.