The instructions are in the folder with the picture. But here they are again...
To insert loadscreens into game, go to...
My Computer
Then into...
Local Disk (C:)
Then into...
Program Files
Then into...
Firefly Studios
Then into...
Stronghold 2
Then into...
ui
Then place into...
frontend
after this simply copy the loadscreen pictures into frontend and start playing the game. Make sure however, to backup the original loadscreen pictures!