Hi Roel, I have a suggestion about tidying up the files repository on this site as follows:
These two are old and possibly no longer useful. Delete.
This could be misleading as it was never a completed and tested design. Maybe tag it as an "experimental prototype". There have been no further updates so it may be a dead project.
This is no longer useful, Batch PCB don't do 4 layer PCB designs. Delete.
Delete as all these are available in the CVS source tree.
Delete as all stuff under that directory is available in the CVS source tree.
This looks like an old quote, may be outdated, not really useful. Delete.