Thank you very much for your fast reply!
You are totally right, we have been working on this script recently and have apparently overseen this mistake. However, we have fixed the URL pointing to the server but the script is still not able to retreive the picture resources. The correct URL should be https://www.ling.uni-potsdam.de/cslmlab/continuation_study/continuation_pcibex_resources/pic_continuation_study.zip for both of the study parts.
We beg your pardon for this silly mistake. But still, can you think of a reason for the problem that we experience?
Thank you again!