This is where I'm at now :
1) Installed DataObject manager (with swfupload) and it went ok
2) I tried to use the code provided by Juanitou and it did something (creating table field when doing dev/build)
Waht I dont' get is taht when I upload a new file in the File&Images section of the cms it doesn't give me a chance to see the "legend" field. I can only see "name" " title" and "content"
Maybe I'm not using thi the right way
Please guide me ;)