Kamil,You should add "return true;" at the end of the custom code to meet the condition criteria.For the use case you have described, I would consider creating a single rule that gets fired on the button click. At that moment it should be possible to pull the values from both inputs using a custom JS code. In other words, if you are confident in JS and do not need to capture the input fields values unless the visitor submits the form, consider a single rule.