To use the Rayus lab interface you'll need to start in the orders template.
From there you'll go to labs and select new. 
In the next window you'll need to select the RAD tab at the top followed by selecting CDI Rayus in the Performing Entity drop down.
You'll then need to search for the diagnosis with the Search All button
The next step is to uncheck Use Nextgen Compendium and use Search All to select a test.
Once you've completed these steps you'll see the test and diagnosis in the bottom panel.
Before selecting Save&Send, make sure everything is correct in the General tab on the bottom left of the window.
Below is what you should see defaulted in the General Tab.
