RE: balancing
Don't know about that particular set-up but every plane has to checked before flying. Unless you've done something way out of normal it's usually just a matter of moving the battery pack, receiver, or possibly the servos until you get the CG correct. In some cases all of that still isn't enough and extra weight must be added where necessary. The manual should (usually) point you in the right direction as long as your engine is within the recommended range.