bnt - the post was my putting my toe in the water, since there had been no response to the previous enqs. hence the lack of info. I'm fairly sure no-one would want the 502 errors posted here.
The issue is using QTGUI with Dev-c to produce a GUI programme. I am certain it is the Dev set up too - it is knowing what to change that is the problem. Anyway - I'm playing with 'Creator' and it looks easier!