will this engine-http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXFV68&P=0 fit in this plane-http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXEDN7&P=0? if so what/ if any modicfications would be needed? will this void the warrenty? will the plane be hard to control?

Should be no problem at all. The engine range is .25-.32 and the engine is a .34. That will not void your warrantee and the .34 will not make it any harder to control than a .32 would.

You sound like you may be just starting out in this hobby. If you are not an experienced flyer, that airplane will be VERY hard to control. You need a trainer, and an instructor. Look up your local RC flying club and take their advice on how to learn to fly.

If you are already an experienced flyer. You will probably like that airplane a lot. Go for it and have fun.

Jim