What springs to mind here is a Linux incompatible Wi-Fi adapter and
the only way to be sure is to test with a different one and see if
that has the same sort of issues. I've had Wi-Fi working perfectly, as
have many others, so it does work with a compatible adapter. FWIW the
ZyXel USB Wi-Fi adapter is 'plug and go' so perhaps it might be worth
getting one of those to verify whether batting your head against this
particular wall isn't going to get you anywhere ?