Wonderful. Glad to see you're working on it until it's perfect 😁

I'm using love2d and the EffekseerForLove plugin. EffekseerForLove has a custom TextureLoader for Effekseer to be able to load the textures using the love filesystem, and the error messages come from there. Here's an example love2d program that loads *.efk from a directory (hardcoded to SC-Astrology as an example), so you could see all the warnings for each file:

 local effekseer = require('effekseer')
 local manager
 local effects = {}
 local handle
 
 function love.load(args)
     love.window.setMode(1280, 800)
 
     -- Pass in true to print warnings, remove true to raise an error instead.
     manager = effekseer.newEffectManager(true)
 
     local path = 'SC-Astrology'
     local k, v
     for k, v in ipairs(love.filesystem.getDirectoryItems(path)) do
         if v:sub(-4) == '.efk' then
             print("Loading: " .. v)
             table.insert(effects, manager:newEffect(path .. '/' .. v))
         end
     end
 end
 
 local tot_dt = 0
 local idx = 1
 function love.update(dt)
     tot_dt = tot_dt + dt
     if tot_dt >= 1 then
         tot_dt = tot_dt - 1
         print("FPS: " .. love.timer.getFPS())
     end
 
     -- Play the next effect if none are playing.
     if not handle or not manager:exists(handle) then
         handle = manager:play(effects[idx])
         manager:setLocation(handle, 640, 400)
         idx = idx + 1
         if idx > #effects then
             idx = 1
         end
     end
     manager:update(dt)
 end
 
 function love.draw()
     -- Draw all effects using the manager
     manager:draw()
 end

You need to run love with the EffekseerForLove plugin in the LUA_CPATH though, so it's not as straightforward as running other love2d programs. Let me know if you want to get it setup and need a hand!