Hey.
In order for myCRED to be able to award points for a user logging in, myCRED must be able to detect a login. Right now, this is done by hooking into the wp_login action hook which WordPress fires when a user has completed the login process and is about to be redirected.
When you use a third party login plugin, the plugin usually overrides the default WordPress process or mimics it in one way or another. Some plugins however just overrides and “do their own thing” neglecting to take into account third parties listening in.
Now, I have not used UserPro so I do not know how this plugin handles the login process. It would very well be that they do honor the login process but myCRED is “too late” and misses out.
As of version 1.4 myCRED also supports the Social Connect Plugin which does things slightly different but offers a handy action hook for third parties to play with.
So to answer your question, I do not know if it works with UserPro as I have not yet tested it but chances are it does. I usually check by searching the plugin file for something like this.
do_action( 'wp_login', $user_login, $user );