Confirmed that it was definitely WPS that was affecting the Linx tablet Wifi connectivity so I've cancelled the return process back to Amazon (using the tablet!) and i shall be keeping the device.
I'm also starting to wonder what affect WPS was having on other Wi-fi connected devices such as NowTV and FireTV........
I can start installing 'stuff' now and give it a real test.
Just for completness these were the error messages that were appearing in the Windows system event log concerning the WLAN-AutoConfig service that led me down this route :
WLAN Extensibility Module has failed to start.
Module Path: C:\WINDOWS\system32\Rtlihvs.dll
Error Code: 126
WLAN AutoConfig detected limit connectivity, performing Reset/Recover.adapter.
Code: 1 0x10 0x4