>Cetin,
>There are two grids on form. For each row in left grid could be few rows in right grid.User want to manualy reorder right grid so that allways rows belonging to first row are on the top, then follows rows for second left row, and so on ... They don't want an additional field which can connect rows in whatsever order in right are they.

Add field for sequence. Add index for sequence. Give user a move up button and a move down button.

For move up:

lnRecno = recno()
lnCurrent = table.sequence
skip -1
lnPrevious = table.sequence
replace sequence with m.lnCurrent in Table
go lnRecno
replace sequence with m.lnPrevious in Table