NOT POSISBLE TO EDIT AN FMS

HI I am working with FM 5.2.1 the latest version: I am working on a rather big fms, 480 slides. Since a few days when I try to edit ( try to center an image, or try to replace a text field. They seems to merge to 1 image file: one just cannot move or edit them anymore. I mentioned this to the App Support Team and they instructed me remove a certain file deep down in the program. At first this did the trick: meaning FM 5 was working again properly. But upon opening the program again the next day : the same annoying thing was back. Performing the same procedure helped. But every time yo close the program it is there again. And Today even worse : even after performing that procedure, now the program is not working properly anymore: one cannot move an image and or text file over an image. Nor does one see the green/ yellow lines that indicate the center position of the image. Has any one came accross this same problem? The Imac runs one El Capitan. Till this is more or less solved I don’t see me working with FM 5 as it is more than frustrating not being able to work properly.
ps Damien West of the Support team is aware of this “problem”.