Some notes on the spin-off update:
To set it up, you should be able to just unzip it over-top of the mod in the same directory. Backup any .civ5mod file to overwrite it if there's an issue. If you've done your own modding to any files I modified, they'd be overwritten also.
List of files in mod adjusted
The increase in costs across the board is still in place. I think it should be gutted anyway but it will impact unit costs by roughly +20% along with buildings and I left it in. Keep that in mind when looking at unit costs though.
If someone wants to change this for units and buildings... this is how.
At the moment, I did not change the vanguard promotions such that they would have access to "siege". This will not destroy any siege promotion selected for a sword-longsword however when upgraded as it's not listed under the promotion swaps to be destroyed. It will destroy the native 10% bonus on swords as intended, that's not at issue versus a selected promotion costing XP. That stays.
I'd rather vanguards have access to siege as it is rather than use this as a work-around (I can't think of a good reason not to). So that's probably part of step two is to work out the way to do that. The sword units and mobile/siege units already have significant advantages as elite units that this wouldn't be a major impediment to build them instead that a cheaper unit could also attack cities and fortified units when upgraded with XP.
I did strip out the defensive terrain bonus for any mobile units. We could discuss which UU(s) might be best to allow this as a special feature for a mobile unit. Berber might be a good pick though.
It remains on infantry, melee, ranged, and siege units (as intended in the mod for siege). Terrain promos remain in but they should get no defensive bonus without those terrain-specific promo for rough or flat terrain and I believe no fortification bonus, but I'd have to test that.
I admit a flanking promo would be interesting, but they're already likely to get a bonus as it is for now that we can make do before making or discussing further changes. It is an option that we could do though without much trouble as added promotion rather than replacing rough or flat terrain promotions.
I stripped out the bireme/galleass getting a city attack boost. Frigates (swapped with galleons) should now start the city attack bonus for naval ranged units. It was extremely powerful to use naval ranged units without a resource requirement otherwise. This is also easy to undo as a change. I just commented them out in the file.
Bazookas didn't get a ranged defence bonus alongside GG/MG? Fixed for consistency but I'm not sure any of them need it.
I'm not sure what the intended strength for XCOM is. I set it at 120 and adjusted cost accordingly. The spreadsheet used for the cost and strength adjustment scripts in the sql file contained an error with a listed strength of 110, but they are currently only 100
in vanilla BNW. Both them and GDR still receive a discount in cost, mostly for giggles rather than balance and it is not as extreme as in the default mod.
Hand-Axe was still really strong for some reason. Adjusted it down to 13/13 (was 20/15). It's basically a slower version of the chariot and a little harder to kill.
For all other changes:
refer back to here