Hi,
I can't replicate this... odd. Are you on windows or Mac?
if your project already has playmaker and it has trouble to update, clean up PlayMaker, by deleting the PlayMaker folder ( make sure you moved out the Resources/PlayMakerGlobals and your templates out of that "PlayMaker" folder first). Also delete the Plugins folder content (just the PlayMaker dlls, if you have more assets than just PlayMaker in there)
When you install PlayMaker from a project that has errors, the wizard is not going to be launched, so simply manually install by importing the package situated in "PlayMaker/Editor/Install/"
Also, it might be good to check if Unity can run the api updater before you do that, maybe that's all that is required: go to the Unity Menu "Assets/Run api updater" if it's not greyed out.
Bye,
Jean