Closed Issue: Can't View My World [43187]

I used TerraMap to view my world, trying to find Floating Islands, and it worked fine. I then loaded my world in TEdit to change the blocks a Crimson Altar was sitting on. I tried reopening my world in TerraMap and now I'm getting this message:

World file tiles list start is not where it's expected to be. Expected: 2612 Actual: 2604

These are the details:

System.Exception: World file tiles list start is not where it's expected to be. Expected: 2612 Actual: 2604
at System.Runtime.CompilerServices.AsyncServices.<ThrowAsync>b__0(Object state)
at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)

Version: 1.3.13.35023


I'm not sure what all this means but was hoping someone might be able to help.