Just curious; What will happen, if you clamp both paint inputs?
Looks like the action is the devil by outputting different ranges and the paint node just reads them normally.
Interesting, clamping the input into the Paint BG makes the issue not apparent, but clamping footage is not a reasonable solution.
Clamping is not the solution (actually in most jobs it is 
), but it’s a fast way to find the connections going over the range.
Can you send your setup please? I’m wondering and still curious if ML is going over the borders or what inside the action is doing so.