BOXes in SAP script

hi,

i am facing some problems in designing boxes in script,

i have designed 4 boxes in main window as per client requirment, these 4 boxes (together) are to be repeated depending on the no. of operations,

1>> condition is if there is no data to be printed in 1 box, that box frame should not be shown, and the next box should go up,

2>> the box height should change depending on the no. of records to be printed in one particular box,

3>> the box to be printed in the next page should be printed in the current page only if there is enough space in the current page.

thanks,