Files "crash" when containing too many png's, resulting in all data in GGB-file lost?

Hi everyone,

Consider the attached file. It works fine in GeoGebra Classic 5, which I have installed on my laptop. However, what I'm interested in, is uploading that file to the web-based GeoGebra applet in order to obtain an activity file which is where the problem occurs. After adjusting settings for the activity file (width, height, allowing pan/zoom etc.) i click 'Done' and upon that I click 'Save and close'. The resulting activity file now contains none of the data that I've put into the file and the attached file that I've uploaded to my online GeoGebra-account is missing all data as well.

In fact I've experienced something similar before (with a different file). What these files have in common (the attached one and an older one) is that they contain png's. So my fist question is this: Is there a limit to how much image-data a GeoGebra file can contain in order to create an activity file? And my second question is: Does anyone know how to resolve the issue? I have tried to make the png's smaller by lowering the quality, but it does not work.

Thanks in advance!

--R

Edit: I have not attached "the attached file" anyway. It is rather large at ~2.6MB and hence it was not possible to upload it to the question. I still hope the issue is clear and that the questions make sense.