One trick to adhear a veneer is by using 5 minute epoxy.

First I wouldn't use the glue on the veneer you bought I would sand it off or maybe you could use some solvent ?

Once you cut out your shape, you would coat the back with the 5 min. epoxy using a small squeege. Let it sit until it gets really tacky and then apply it and burnish it down with a roller. You'll get an unbelieveable bond. Don't forget to prepair the mating surface with some sanding. You can then sand it thin (carefully) and coat with epoxy, building up a smooth surface.

If you call information and get a hold of Constantines in Bronx, NY. They carry all kinds of exotic veneers in all sizes. Maybe they have a web site?