Importing Player Templates

I created some standard SL Player Templates for my team and used the Export option in the Player Properties window so could save the template files (the .xml files) to a common folder from which all my team could import it into their projects. This was working fine up until recently. I started getting an error last week while working on a SL file. It is the error message "Available Memory is Low - It is strongly recommended you close any unneeded applicatoins and save your project". It appeared when I clicked the Player button in the toolbar. The message is deceiving because I had no other applications open and tons of memory available. I have also easily worked on much larger files than the one I was currently working on (only 12 slides). I was still able to work and save my file, but could not preview or publish it (it starts to preview but then the progress bar locks up). I checked this Forum and found a number of proposed solutions. I tried copying and pasting my slides into a new project. This worked, but required a fair amount of editing since it does not paste over accurately. I then played around and tried the 'Import' option from the Articulate logo sub-menu to move my "bad" file into a new project. This worked extremely well and I did not have to do any edits afterwards. However, once I saved the project, closed, and then re-opened it, I got the same nasty error message again when I clicked the Player button. After consulting with my team who work with SL, we ran a number of tests and have narrowed it down to the actual Player Templates I created. They were working fine a few monthsa ago, but now whenever I Import them or select them from the 'Open' drop-down menu  in the Player Properties window, save and close the file, and then re-open it - I get the error. I have no idea what would cause 4 Storyline Player template files to become corrupted all of a sudden, but it appears that this is currently a risk.  I then imported a template (.xml) that one of my other Learning teams created and it worked okay (I did not get the error message), but the Logo did not import.  So, I will be recreating the Player Templates, but rather than export them to an .xml file, I will save them in a blank project (just one blank slide) as a .story file. This appears to be a safer and more secure option.