In this paper, a short summary of the formulation of absolute nodal coordinates elements, including beam, plate, and large deformation solid elements, is given and two aspects of the integration of the elements into a general-purpose flexible multibody system, i.e., constraints and contacts, are studied. As an alternative to the constraint method for coupling flexible and rigid bodies, the direct assembling of nodal absolute coordinates into those of rigid body's is proposed to simultaneously reduce the number of system generalized coordinates and constraint equations. To enable the contacts between flexible and rigid bodies, the shape of contacting bodies are represented with basic geometries including sphere, brick, cylinder, and triangular patches, and the collision detections between bodies are converted into those of basic geometries or tessellated triangular meshes of the outer surface. Several numerical examples are carried out to demonstrate the effectiveness of presented methods.