Openerp 6.1 modules directly can not be used in openerp 7. You have to do some basic changes in openerp 6.1 modules. Like tree, form tag compulsory string and verision="7" include in form. If you have inherited some basic modules like sale, purchase then you have to do changes in inherit xpath etc. Some objects res.parter.address removed then you have take care of this and replace with res.partner.
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