Check on ip-adress.com for example if it doesn't show your real IP and it shows the IP of your VPS, but the same time some websites detect your proxy and show your real IP, then the problem is with ProxyCap.
Not actually a problem, probably it's just giving every website you visit a message (called headers in a HTTP request) containing your real IP. That's what some proxy clients do as usual... .
Also there are other ways, like your Gmail account to prove that you're from Germany, so check that out, too.