Why does it keep getting stuck on Checking to ensure login?

[Kad]

Stealth Buyer Pro

When I put all the info and proxy, and click Login, it stays forever on checking to ensure login...
any help please?

Note: I disabled the proxy, and logged on with my main. It worked.
Then I tried to do it with another account and another proxy, it log-ins but it won't show up the NPs.

Will fully rep if you help me.