Questions and answers about ERM scripts for WoG.

Gentlemen, I have a question for you. I tried to understand the ERM language, found a few examples, but it didn't help. The point is this: for a multiplayer game played on a randomly generated map, I need a script that changes the portraits of the starting heroes of all players to specified ones (PCX images, pre-placed in the correct directory). The problem is that initially, it is unknown which starting hero each player will have. Can anyone help?