The cause and effects explorer was removed in a recent version to be overhauled for a future Update, though not 9.0.

- New Government system: Constitution
- New Government system: Elections and Elected Titles
- New Government system: Demographics and Wages
- New Government system: Laws Part 1: Using the system
- New Government system: Laws Part 2: Taxes, Ownership, Property, and Wealth
- New Government system: Laws Part 3: Tour of different actions, and Executive Actions
- New Government system: Districts
- New Crafting: Work Parties
- New Crafting: Labor System
- New Crafting: Modules and Efficiency Redesign
- New Crafting: New Tech Tree
- New Building System: Hammer and new Building Styles
- New Mining System: Mineral Dispersion and Drill Usage
- New Mining System: New Processing Path and Pollution Info
- New Animal System: Attacking Animals
- New Ecopedia Syst...
Yeah, definitely set it to No Collaboration. You can select multiple specializations - they are gained at a base rate every day, plus a multiplier (that you can upgrade through food and housing in the game) and that setting changes the base multiplier. If you're only 3 people, you'll need lots of specializations each to fill out the needs of the tech tree. Generally, the games' wiki, https://eco.gamepedia.com/ is a great resource since it explains a lot more than the ingame text.
Please no longer link to gamepedia, we stopped our cooperation with them and the wiki is no longer official nor endorsed by us or worked on by the former wiki admins. We use https://wiki.play.eco now, without ads and recent software. It also allows anyone to edit, without permanently required approval by Wiki-Admins nor with the requirement to register. Registered accounts get patrol rights automatically after a while, just like on Wikipedia.
Not without cheating them in or finding them on another island. That problem is supposed to be fixed in alpha 9. If it ever releases.
Indeed, Update 9.0 allows you to use any seeds for the farming book. The spawn rate of seeds has only been slightly adapted, though, as it's intended for them to be taken care of by farmers with the respective specialty.
While the veins are indeed very big, them being on the surface is a bug that is fixed in newer versions.