rule input submit(boolean) but always mapped to process variable(text)

Your post is very unclear - could you try re-phrasing, and/or simplifying?  What is your use case / what are your step-by-step expectations / what issue(s) are you experiencing with each of those steps when you try?

it was not about that you should give up. Its about that we shouldn't have the same discussion three times of the same author. :) we can support you well, if there is "only" one thread.

then please tell me why there always null value for the data input?

did you check if your sail form is delivering the variables to the process? What is the process history telling you regarding variable updates?

tell me what is sail form? sorry English is not my first language though i went college in the USA, 

It didn't report any variables in the process, just said you can't input any null value some etc similarly.

No offense, but did you do the academy courses.? There are terms epxlained like sail form, constant etc,

my major is not computer science, and i never heard any instructor of mine even said "sail form"

but i do know what is constant for software development:)

the node wants to store a process variable. -> This process variable has to get the value itself form the form. So the form needs to "transmit" the value from the textfield to the rule input of the SAIL Form and the user input task from the SAIL form rule input to the process variable. -> so i would suggest you check if the start node is properly maintained and transfers the variables properly to the process.

the node wants to store a process variable. -> This process variable has to get the value itself form the form. So the form needs to "transmit" the value from the textfield to the rule input of the SAIL Form and the user input task from the SAIL form rule input to the process variable. -> so i would suggest you check if the start node is properly maintained and transfers the variables properly to the process.

there you see its just updating the variable submit and "aa". not the variable "username" , so the value stays NULL -> this means you try to save a null value which crashes your process. 

I know, but why username doesn't receive any responding values since I already let ri!username.username,ri!username.password write in saveInto?

I delete the "aaa" value, but it is still not let the values process through, so I don't think that is the problem.