So, one step further, with the new Beta everything went fine. Started to build a new product. Outline: Want to build a Gallery, where owners can add postscript-pictures with some comment. A thumbnail is generated and a page with thumbnail and comment is displayed. The thumbnail is a link to the actual Postscript picture. A Gallery can include other Galleries to collect pictures for different topics. This will be a subclass of a Folder. As this product should be used by many different users, I don't want to fill up the database with all this pictures. So I want to make an object, which acts like a file, but stores only a link to an external file. Subclassing File and overwriting PData -> ready is the BLOB. Q1: Is there already something like this in Zopeland? This could also be used to make dataviewers for big (GB) datafiles. Q2: I can delete the object from the POS, but how do I delete also the external file? Is there some hook I can use? Q3: The development of a package is quite time consuming, because I need to delete the product, restart the server and add the object again. Can this be done faster? How are other people developing packages? Are all writing bug free code :-)? Q4: Would it be easier to build soemthing like this as external methods? I see now, that it is easier, but than I need to implement my own upload scheme and so on. (This are some of the benefits of a product, all the predefined protocolls, right?) Q5: If I want to extent the gallery with some functions, can these be coded as external methods and added to the Gallery object? I have tried it, but a BLOB object, which is only one class of the product does not get the method (defined by def method(self,...): ) Q6: If more and more packages are developed the security screen becomes rather big. How will this be handled in the future? Thanks for any help and insight you can provide __Janko Hauser