Motion does not allow duplicate object names. If you start an analysis on a system that contains duplicate names, the ID of the object is appended to the duplicate name internally. For example, if two Marker names are both "MarkerName", then one Marker will be renamed "MarkerName[ID]" and the other will be renamed "MarkerName[ID]".

Spaces and some special characters are not allowed in object names. Spaces and disallowed special characters are replaced with underscores ("_"). For example "Function Expression#DM" will be renamed "Function_Expression_DM". Allowed special characters are: [,], _, !, ~, %, ^, &, and = (comma, underscore, exclamation point, tilde, percent, caret, ampersand, and equals sign).