how do I edit lights so that I could have custom strobes and all that? Or glows for ship engines?

there found in the fleetops.spr file just look for the entries for warpglowspriteblu6 (or summit like that

@sprite_node Warpglowspriteblue6 flare_glow_soft const (6,6) (0.06,0.06,0.12) billboard

@sprite_node = needed tells games its a sprite node (obvious)
Warpglowsprite6 = name of sprite
flare_glow_soft = texture reference name (fleetops tend to use the texture name for this but a2 dosent)
const = sprite effect (const means it stays on with no flicker)
(6,6) = glow size
(0.06,0.06,0.12) = glow colour in rgb format
billboard = makes the glows appear sphere (if not present then the glow will stay facing the direction of the node ideal for long nodes)

EDIT

to add/remove/repostition sprites on meshes ingame u will need to import the ship into a mesh editor. if you want to add sprites to ships with animation u can do this by making a blank sod with the sprites in the correct postition and use the overlaysod code to attach them (only works if u want to add sprites)

if you want the sprite to appear after the ship is built and not appear with the debris u need to place the node under the lights node on the mesh