lag = high ping
Tell us your ping in-game.
test your ping on server where server is located.
If it has ping over 100 you should switch to different DNS.
I am using google for example.
If you have performace issues (slow cursor,low fps, scrolling speed is very slow, game freezes, choppy animations)
Its probably cuz of CPU or RAM.
I dont know why, but Fonline has insanely high CPU requirements.
You probably have just some overheating problems.
But try everything. Run it in small resolution, try OpenGL, Direct. Lower your max fps in config file.
And bring us back results what you gave us isnt much.