• Setup an event that fires whenever a system controller changes (in the event of war or the system being traded). If there is a trade nexus present in the newly acquired system, it will delete automatically (unless you do not have your own, in which case, you'll need to dismantle it manually; ai will delete automatically regardless). This should prevent situations where the AI acquires the homeworld of an enemy (and thus their trade nexus) and gets an artificial boost to their trade until their yearly recalc event fires.

• Small update so that when you load in a game, it doesn't automatically build a new trade nexus (for a player only) if you have already opted out of the system by dismantling your own. Should help prevent situations where the player sometimes gets two trade nexuses.

• Addressed a bug that was preventing influence cost for some diplomatic pacts. Thanks to Aliénor for catching this!
  
  
• Mod now properly overwrites vanilla pirate events to only fire for players, rather than AI, in the unlikely event the vanilla trade system kicks back in (would only happen if a trade nexus is dismantled on purpose by a player or an AI loses their capital, and needs to rebuild one, which will happen within the year).

• Added some extra notes in the megastructures file to help with creating personal patches with other mods.
  
  
• Added a country_flag event at the start of the game, trade_nexus_mod_active, so that other mod creators can use it if needed. This is now a prereq for building the Trade Nexus, which allows other mod creators to use the market_capital megastructure in their own mod for patching purposes, if they wish to.

• Further optimized the variable calculation by removing an unnecessary step I had.
  
  
• Changed the modifiers on the trade hub to be triggered, so that in the event the player opts out of the trade nexus, the trade hub will revert back to vanilla (+1 trade range collection).
  
  
• Added in two event overrides, pirate.4 and pirate.5, to trigger only for players. This should prevent those events from checking every AI empire for trade being intercepted, instead just firing for players. In the event the AI loses their original trade nexus, and reverts back to the vanilla trade system until a new one is built (no less than within a year), they are not at risk of pirates. I cannot prevent the event entirely without overwriting the entire on_actions file, which is beyond the scope of this mod.

• Moved the -1000 penalty to trade range, collection, and protection directly to the Trade Nexus megastructure. This means I no longer have to overwrite the Empire Base modifier in Static Modifiers, making it that much more compatible with other mods.
  
  
• Set up the mod so that the player may opt out of using the Trade Nexus, returning them to the vanilla trade system. You just need to dismantle the Trade Nexus and the vanilla system will kick in. You may choose later to rebuild it if you like and the modded system will work again after about a month. This also means if you have any mods that alter trade policies, they will work if you return to the default trade system (essentially building in compatibility). The AI will continue to use the Trade Nexus, which will still help prevent trade lag.
  
  
• Fixed Commercial Pacts and Federations not benefiting from trade. As an added bonus, automatic commercial pacts created via Federations now properly display in the tooltips as Commercial Pacts under Energy.
  
  
• Further optimized the code and calculations. The AI now recalculates their trade value once a year, instead of once a month. The player will always recalculate their trade value monthly.

-Added additional supports for the AI to guarantee they always have 1 market, no more, no less.

-The trade nexus now builds automatically above your homeworld for a more seamless start at the beginning of the game. You can dismantle it and rebuild it elsewhere, however, should you not want it there. If you start the game on an existing save, you will still need to build it manually (as will the AI, which they'll do right away).

-Orbital Trade Deposits 1 through 5 now generate a combination of energy and minerals instead. This is to help reduce the clutter on the galaxy map caused by these random trade deposits. This doesn't affect trade value generated on colonies.

Thanks to Dr. Nolegs for the above suggestions!

Initial upload