Thanks for the link. So from what I understand there are two things you are asking about here:
1) The submit button not disabled if reCaptcha is not checked
For this, the plugin currently does not disable the submit button until after the form is submitted. I will take another look for the next update if there is a way to add validation for the reCaptcha field, or maybe just disable the submit button until it is checked, as you suggest.
2) The post content field does not remember any user entered data
This is what I was referring to in my previous reply. It sounds like something is interfering, probably another plugin or it could be something the theme is doing. Normally the post content field (even with the RTE enabled) remembers/returns whatever data the user had entered. If it would help, I would be glad to provide a video that shows this working on default WordPress latest version.