The AOE3 editor was supposed to be built on the engine of the AOM editor but some functions were lost in the translation. Sadly, you just can't use simple modifications to boost your units. You have to do it in a roundabout way. For instance, if you want to boost your cav attack, you can activate multiple copies of the cav tech HCXPSiouxCavalryCombat for that player. You can figure out the rest just by looking through the Home City boosts and upgrades and picking the one that fits your needs.
Warning: if you are playing a long scenario and want to save and continue, all your boost will be gone when you restart. Another quirk of AOE3 that messes with scenarios.
Crunkatog on ESO
Bart331 balance suggestion: aztec: remove civ
Voltiguer: Ender, Sioux in 1.04 will be a top civ, no matter how many layers of Sioux goggles you put on
schildpad on Elephants: ...their mansabdar unit sucks so hard it looks like a black hole
Crunkatog on Steam.