Locked Custom Cups

[PolloConMole]

These days I download many custom cups, for example MK, all-tracks and several others. The problem is that there are some cups that I can not play because they are locked, does anyone know why
What do I have to do to unlock those cups?

[ZipperZbieracz]

I think custom cups may have certain prerequisites necessary to be met to unlock them, just like silver/gold/plat cups? Ask under the cup uploads why they are locked or find a readme for those locked cups if there are any.