arXiv:2608.04971v2 Announce Type: replace Abstract: Immersive exhibitions increasingly combine large-scale projections with mixed reality (MR) head-mounted displays (HMDs), but how users perceive transitions across these heterogeneous visualization environments remains underexplored. We investigate cross-reality (CR) object- and scene-level transitions in a hybrid immersive art installation spanning projection, augmented reality (AR), and virtual reality (VR). In a within-subjects study (N=24), we compared a calibrated condition with a bundled inconsistency condition introducing noticeable differences in spatial alignment, visual appearance, and cross-device latency. This contrast was used not to establish perceptual thresholds or hardware targets, but as a diagnostic probe to make transition disruptions more perceptible and discussable. The inconsistency condition reduced presence and increased workload. Interviews showed that spatial misalignment disrupted action-outcome predictability, appearance mismatch reduced aesthetic coherence, and latency weakened perceived responsiveness. Effects also varied by asset type: rigid static assets exposed inconsistencies more clearly, animated skeletal assets shifted attention toward motion, and particle effects often masked small discrepancies. These findings clarify how users perceive projection-MR transitions and support asset-aware design strategies for coherent hybrid immersive art. We also release HUICRSync, an open-source Unreal Engine plugin for prototyping projection-MR CR experiences.