I'm not going to argue about the dire situation of the Wii U in Europe because it's true but that chart (the one in the link) doesn't prove anything. It's a monthly chart and SM3DW was released on the second to last day of the month. Moreover, it only has 10 spots and some of them are taken by multiple SKUs. My point is that the only thing you can do with that chart is congratulating the games that enter it and not much more.
Well, I'll link you the December table when it's on the page. Sadly, that's the info we have right now.
And still, it's a top10, but Spain is no UK. Games don't sell as well but if using the (Nintendo) released hardware charts is useful to have a good image about the WiiU in Spain, here you have
this link.
One of the problems in this charts is that the Wii is still selling (is cheap, Spanish economy is not in good shape, people don't know what the hell a WiiU is). It has covered until May, but Summer has probably been brutal for the console and even if SM3DW has had a decent marketing campaign (I've seen quite some adds on TV) its sales have probably been eaten by the PS4 and the PS3. The latter has been promoted quite agressively this holidays, with it being at 169 since October until November and 149 since December 25th until January 6th (and most spanish christmas gifts are given in the second date, it's a tradition).
I mean, I'm not going to say "I don't know anybody who has bought a WiiU" because it's anecdotal evidence, but it's obviously not in good shape at all. You just need to go to any store and you will see it.