I had similar assertion failed error messages today. I am fairly new to Codesys. I tried using SFC for the first time, I usually use ST. Anyway I had errors in some of my transitions. I copied and pasted transition code and forgot to change the target of the code. I started getting lots of the assertion errors but now I have sorted out the problems and it compiles OK the assertion error messages seem to have stopped. There do not seem to be any other responses to your post, did you resolve your ...