When doing polar align, have you tried using your main image system or your guiding system?
As the polar align uses the solver, the first thing to do is to solve the polar region, to be sure that all the configuration files are downloaded. This is one of the first thing to do in relation to you telescope and camera (do both prime telescope and guider). The best way is to declare you telescope and guider focal length in the mount page (you can save several configurations).

In the align window you have a configuration button witch brings you on the specific page to download configuration files. As the FOV is know, the good files to download are easy to identify (green signal toward each file).