Hi servernerver,
i posted this for reference to the devs to fix it in the next release.
I am happy to post my own fix until then, because there's an error in the showproduct.tmpl
Open the showproduct.tmpl (if you use vb3enhanced, you will have to edit te one in the vb3enhanced-folder) used in your installation -
Find:
product=$id
replace with:
product=$product
and it will work for you

(hopefully)