Need Help for Build an Application

I'm looking for help to build a .deb package and security reports for a web application from source code. It's an Onlyoffice fork without connection limits.

*Basic informations:
-Repo: https://github.com/btactic/document-server-package
-Documentation: https://github.com/btactic/document-server-package/blob/btactic-documentation/README-BUILD-DEBIAN-PACKAGE-NO-LIMITS.md

*What I need:

-Report from a good Static Application Security Testing tool (SAST) (can be open source tool) and an overall analysis of the code security and its dependencies;
-Detailed instructions (tested) for build and run the .deb package for the Onlyoffice Document Server on a virtual machine (Debian 11 Server with 16GB RAM).

OR

-Detailed instructions (tested) how to remove the connection restrictions (originally limited to 20) of the official project (https://github.com/ONLYOFFICE/document-server-package) and build and run the .deb package for the Onlyoffice Document Server on a virtual machine (Debian 11 Server with 16GB RAM).

Note: I will use the Document Server for integrate with Nextcloud.