Hello Traktor,
Advanced random map generator cannot make allies. This is done either in the editor manually or by using the H55 feature in the game.
Here is how to use the feature:
1. Launch the game, go to Multiplayer -> Hotseat
2. Create a map with 2 human players and 2 computer players.
3. start the game
4. on day 1 the first active player will be asked if the game wants to team all human players vs all AI players. Select OK.
5. start playing your game as usual, in 2 turns both players will have shared vision and will be allies.