Hi...
If the character is moving around the screen then you must have used Move (M key) at a frame other than frame 1 on the Timeline.
To avoid this just start a new project and don't use any of the transform keys such as Move (M), Rotate (R) or Scale (S) from the left side toolbar. This will keep the character centred. However, if you do want your character to be in a different position, just make sure that you position the character at Frame 1 only.
Peter
Forum Administrator
www.reallusion.com