Can i upload siemens HMI?

hi All

I would like to verify and expand my understanding of the HMI upload functionality.

1. Does siemens hmis (i am asking in general no specific model) allow an upload of the runtime file for backing up?
2. Does siemens HMIs allow compare between compiled project files and uploaded binary file from the HMI? if yes what are the steps?
3. I assume no siemens HMI allows to do the upload which then could be used for the development - is that right?
4. Is the backup given on site which is not 100% trusted - what steps shall i take ? Shall i do upload of the binary file from the HMI just in case and then download compiled project to the HMI to see if it works? Nothing can be 100 percent tested so i assume if possible compare of uploaded binary file and compiled project should be done - would they match or there will always be a difference ?

1.) Yes

2.) NO

3.) Wrong

4.) download the project you have