I recently experienced some problems related to opening and saving prp files in PageEditor:
Once I opened a file/age in it, when I hit "Open" again, I can choose another file, but it does exactly nothing after closing the file open dialogue. Some revisions ago it used to close the currently opened file and then open the new one. The best would be if it behaved like PrpShop and added the new files to the ones which are already opened, so that one can edit all of them.
There also is a problem related to chaning the PRC: When I edit the code and then switch to another object without hitting "Save", it forgets the changes I just did - I have to hit "Save" once for each object I change. If that behaviour can not be changed, it would be cool to at least have a warning like "You have some unsaved changes in this object, do you really want to discard them?". In addition, for some prp files I have the starnge effect that each time I changed and saved it, it got about 100 Byte bigger. If I reverted the change, it grew another 100 Byte and so forth.