Yes that example shows your link in the vbulletin options was not a full url and as such fixing that link in
vb options would have worked or simply hard coding it also works.
Goes back into this whole discussion of relative links. You can not use relative links in code and show that code over another directory outside the normal forum structure without the links being full urls. The links would never show right because a relative link tells the code to look for that file etc in the directory where you are at.