Correction - there are 9 compiler errors, across a few different files...
For sake of completeness, I'll post them all here - I dunno what has caused this but as you can imagine it's pretty scary to just suddenly not have Unity any more - Is there an easy way to undo the import?
Assets/PlayMaker Utils/PlayMakerUtils_Events.cs(14,28): error CS0111: A member `PlayMakerUtils.SendEventToGameObject(PlayMakerFSM, UnityEngine.GameObject, string)' is already defined. Rename this member or use different parameter types
Assets/PlayMaker Utils/PlayMakerUtils_Events.cs(19,28): error CS0111: A member `PlayMakerUtils.SendEventToGameObject(PlayMakerFSM, UnityEngine.GameObject, string, HutongGames.PlayMaker.FsmEventData)' is already defined. Rename this member or use different parameter types
Assets/PlayMaker Utils/PlayMakerUtils_FsmVar.cs(25,28): error CS0111: A member `PlayMakerUtils.RefreshValueFromFsmVar(HutongGames.PlayMaker.Fsm, HutongGames.PlayMaker.FsmVar)' is already defined. Rename this member or use different parameter types
Assets/PlayMaker Utils/PlayMakerUtils_FsmVar.cs(82,30): error CS0111: A member `PlayMakerUtils.GetValueFromFsmVar(HutongGames.PlayMaker.Fsm, HutongGames.PlayMaker.FsmVar)' is already defined. Rename this member or use different parameter types
Assets/PlayMaker Utils/PlayMakerUtils_FsmVar.cs(163,28): error CS0111: A member `PlayMakerUtils.ApplyValueToFsmVar(HutongGames.PlayMaker.Fsm, HutongGames.PlayMaker.FsmVar, object)' is already defined. Rename this member or use different parameter types
Assets/PlayMaker Utils/PlayMakerUtils_Serialization.cs(109,30): error CS0111: A member `PlayMakerUtils.ParseValueToString(object, bool)' is already defined. Rename this member or use different parameter types
Assets/PlayMaker Utils/PlayMakerUtils_Serialization.cs(114,30): error CS0111: A member `PlayMakerUtils.ParseValueToString(object)' is already defined. Rename this member or use different parameter types
Assets/PlayMaker Utils/PlayMakerUtils_Serialization.cs(197,30): error CS0111: A member `PlayMakerUtils.ParseValueFromString(string, bool)' is already defined. Rename this member or use different parameter types
Assets/PlayMaker Utils/PlayMakerUtils_Serialization.cs(467,30): error CS0111: A member `PlayMakerUtils.ParseValueFromString(string)' is already defined. Rename this member or use different parameter types