Can't use Photon PUN on existing project.

Hi, when I try to import Photon from Asset Store to my existing Unity Project (which was successfully converted from Unity 4 to 5) I'm getting following errors (without actually writing any code):

 Assets/Photon Unity Networking/Plugins/PhotonNetwork/NetworkingPeer.cs(210,27): error CS0029: Cannot implicitly convert type `System.Type' to `Type'
 Assets/Photon Unity Networking/Plugins/PhotonNetwork/NetworkingPeer.cs(222,27): error CS0029: Cannot implicitly convert type `System.Type' to `Type'

Also there are is no Photon entry in Unity's Window menu, however when I created new project and imported Photon asset, after clicking OK on API Incompatibility thing (which I again, don't have for existing project) I don't have above errors, and can use Photon's wizard from Windows menu just fine.