I am not familiar with Dephli, so are the objects that should be recognized with the plugin by default? If they are, then you might consider making sure you launch WinRunner prior to the applicaiton, or place a call with support to see if maybe the installation didn't happen as it should have.
Did you install 8.0 over a previous version of WR? You might need to take alook at the KBA#5485 on mercury's site to make sure one install isn't affecting the other.
If these are new controls that aren't to be dected ingerently in the add-in, have you tried mapping them to known control types via the GUI Configuration tool? If not, please visit the User's Guide Chapter 9.
The controls I have problem with are not the standard or system controls. This is a third party control set desidned by DevExpress. Yes, I tried to map those controls through GUI Configuration tool, but WR still doesnt recognize them by self. Every time I'm coming back to previously defined window WR says that controls are missing. The same with the spy it does not match controls even if they are defined with GUI configuration.