Re: Multiple registration pages
Look at your bp admin section, you will see the custom profile link you use that to create new groups and fields, as long as a new group is created under the ‘Base’ level then it will appear on the registration page.
As a workaround I would move the three type selections labeled ‘Fan off’? to just after the primary details and use the tree types as just that to confer a user type to each member but also run a simple jQuery show/hide on the further groups so all are hidden and then a check is performed to catch the radio selection and the appropriate group revealed with perhaps a ‘none’ control selection default.
The proper approach would be to complete a section and then pass the form control fields in a session or buffer to the next view to complete further sections but with BP that will likely start to get complicated, as techguy says there is no quick easy way to do this but with client side scripting it wouldn’t be that difficult.