Q7: How can I make blocks ignore/accessible to other players? A7: You can use the Allowlist Module for this. Rightclick the module, type in the player's name, then click "Add". After that, (sneak-)rightclick the block with the module in order to add it. Alternatively, instead of adding a name, you can also check the "Affect everyone" checkbox, which means every player will be added to the allowlist module automatically.
Another option that is helpful if you want to share all of your blocks with your friends: You can enable team ownership in the mod's server config file, and add all players to the same scoreboard team (/team or /scoreboard teams depending on your version). This will cause all players on the same team to own everything that any player on the same team owns.
fiery bough