I've just upgraded to PlantUML version 1.2017.12 from version 8041 and now \n does not work sometimes. In the (cut-down) example below, the Rule defined in the statechart just shows \n literally, but the OnEntry text in the initialState renders \n correctly as a newline. If I move the Rule text down into the InitialState and change the reference then the \n is rendered correctly.
@startuml
skinparam state {
backgroundColor White
backgroundColor<<softwaremodule>> #CCDBC8
backgroundColor<<signal>> #DE8C73
backgroundColor<<statechart>> LightYellow
backgroundColor<<statemachine>> LightYellow
backgroundColor<<state>> LightYellow
backgroundColor<<initialstate>> LightYellow
BorderColor<<initialstate>> Black
}
skinparam shadowing false
skinparam defaultTextAlignment left
state "**«statechart» Master Switchgear Model - Logic**" as 8E437FA1B6DC905 <<statechart>> {
8E437FA1B6DC905 : **Rule:**\n if ('openStatus') then\n 'switchgearStatus' := $OPEN$
state "**«statemachine» smSwOp**" as 6D4FA3B201978C <<statemachine>> {
[*] -[#blue,bold]-> 368F54ED2A907
state "**«initialstate» stInit**" as 368F54ED2A907 <<initialstate>> {
368F54ED2A907 : **OnEntry:**\n 'operatingMode' := $Switchgear Model Initialisation$\n 'setOperatingModeInfo' := $Set 1 for Auto Mode, Set 2 for RTDS Mode, Set 3 for Manual Mode$\n
}
}
}
@enduml