(a) So the gust value for any wind must be considered, correct ?
I don't know that you will be able to pin down a regulatory reference as easily as you might desire. However, consider what your response might be at the enquiry when you are asked why you decided to launch or land with the reported wind at XYZ ?
Consider, also, that the forecast gust is a statistical animal and the expected maximum gust levels are somewhat higher ...... me, I'd tread a bit warily in gusty, limiting conditions .. generally one can come back and try again after diverting. At the end of the day there is no room for heroics in the absence of pressing (non-commercial and real) need ..
(b) What about max cross wind?
Not a major problem philosophically. I have been involved in just this process in the past and my present fleet aircraft has a low priority project in train to do just this ...
Consider that you will need competent engineering assessment as to whether there may be any structural considerations to address. Then, it's a matter of finding suitable conditions for a test program utilising appropriate TP personnel in association with the Regulator .... If all goes well the end result is a mini recertification of your birds to reflect a higher demonstrated value or limit, according to the flavour which the particular Regulator adopts ...