I don't know much about Pagerank but if you are looking to get clicks, Myspace isn't your best bet. Its becoming somewhat of a dying system and you might want to try Twittering the link or finding the niche market for your product.
actually I've seen an increase in clicks from myspace but sorry about your decrease of clicks from it, better luck next time?
myspace links are nofollow they don't effect your pr in any way. It will crease the traffic if you do a good job.
If you want traffic for your website do not go for myspace, use twitter or facebook for instance traffic, I am using both the networks for the promotion of the website.