Hi EtxWaffleBossAl! Litematica should be okay to use, so long as you only use it for schematics and not printing, and replay should be okay in general. If you'd like to reference our forum page of mods you can visit it
here. A good rule of thumb though is if it provides (or has the ability to provide) an unfair advantage to you over other plays, then it is disallowed. You can make a ticket on our
Discord if you'd like to know the specifics of your ban or you may create an
appeal on our forums if you would like to dispute your punishment. If you have any other questions feel free to reach out to me or my fellow staff members. Hopefully, though, I have answered any you may have had.