@Hudsonkm I was just troubleshooting this same issue with the Mastodon. The problem is with the "L" being lowercase in the name of the engine in the engine ignitor config file.
//It should be this
@PART[LiquidEngineKE-1]
It's the same problem with the RK-7 and also RV-1 in that same config file. Change the "l" to "L" in those names and engine ignitor should start working for those engines.
@linuxgurugamer I absolutely would love the EC requirement removed. For me the requirement bugs out way too often.