Noel had made mention when AUX tracks were introduced that cwp files were no longer backwards compatible (that spanned the AUX track introduction). I am not sure if that also affects bundles, but seems it would apply to the cwp file inside of it (whether it will extract the wav files would need testing). Up until that point, a cwp would open as much as it could, tell you it was created in a newer version, and let you know what it failed to open.
Doing a "save as" in platinum to a new folder and copying the audio with the project might be a better strategy than using a bundle. Exporting stems would be the safest, since any DAW could use those.