Is the module report designer available with version 7 ? Maybe an other one to replace it ?
The report designer is available in v7. It's the module called base_report_designer.
It works on OpenERP online and on OpenERP On Premise.
By default, OpenERP Online use an OAuth authetification mechanism but you can also assign a normal password to your user to allow external plugin to connect to your instance. So, if you want to use the report designer in v7, you must assign a password to your user user the top menu:
More > Change Password
You have the reportdesigner in the 7.0 but only for the on-site version and not on the online version because we use OAuth and the reportdesigner only uses the login/password for the access.