Hi,
Thanks for using 3DNA, and for posting your questions on the Forum.
Were you able to repeat the sample applications of x3dna_ensemble distributed with 3DNA?
Please provide a (minimal) reproducible example so others can see exactly where the problem is in your case. Lacking that, the error message "mismatch between base-pair info and model file" may give you a hint.
Best regards,
Xiang-Jun