Problem solved
Thank you very much Jimmy Wu for replying to my post.
I am pleased to report that I have republished the web site to my remote server that I use for "live" testing and all the pages that I created run and load OK - so it seems that I have been lucky this time.
I don't think it was the WA activation server that was causing the problem, it was some corruption in a file on my PC that was trying to access the server. Trouble is I don't know which file was corrupted. Somehow by having both DW and the extensions launch "off line" the corrupted file (or files) was (were) fixed.
The database connection issue was "unconnected" (forgive the pun) being a plain simple typo in the remote connection php, that once corrected fixed the databse connection problem.
P.S. Thanks also for answering my question in the Security Assist forum - I will try out the fix you suggest tommorrow ('tis 11pm here now)
Best wishes
Don