Marriage certificate with translation is needed.

Resubmit with the I485 receipt. Should be accepted.

It is not advisable to travel internationally. Consult with an attorney for guidance.

Yes you should be ok with travel with passport as is and valid GC.

The misspelling shouldn’t be an issue for reentry purposes.

You can request correction on DS260 before or at interview.

No this is likely not the case and just a correction to the online system.

Yes you should be able to but best to work with a family law attorney for guidance.

Travel should be ok with original receipt notice.

Contact NVC directly to inquire about next steps.