This scenario is surprisingly easy. You have a decent starting position and the goal is simple. You can easily conquer Europe, and traveling to the other continents is a piece of cake.
Place all your initial reinforcements in Europe; conquer the continent on your first turn with a surge attack to West Europe. On my second turn, I made several alliances so that I wouldn’t have to worry about losing Europe to yellow. I have strong positions in Asia and North America now; three more continents to go.
Next turn, I again make alliances and this time focus on eliminating red from Africa. Though red slides past me to Egypt, I have divided his empire, weakening him greatly. I now have all of Europe and troops in every continent except Australia; if I can break through green’s defenses, I will win the game.
Instead of this happening, I was unable to take control of either Siam or Argentina, and yellow makes it into Europe with a surge attack. I spend my next turn recapturing Europe and annihilating red. Both ventures are successful, and I still have troops in every continent except Australia.
Though I have violated my alliance with yellow with my surge attack to North Africa, causing him to declare war on me, he is now too weak to be any sort of threat. By trading the cards I won from red, I have enough troops to defend Europe and break into Australia. Victory.