This issue is one of the reasons why I still use Poser Pro 2014 to save my models and products.
In poser 11, if you for example rename an obj file and load the model, Poser can't find it and will ask you to locate the obj. If you do that the model will load perfectly by using the renamed obj file. However if you save/overwrite the model it still saves the old obj file name and/or path.
The other reason I still use Poser Pro 2014 to save my models is that when you save a rigged (character) model in Poser 11, the programmed master parameter control dials won't work for DAZ users. Loading and saving/overwriting it with Poser Pro 2014 will fix that issue.