The errors have to do with the database and you have to just narrow them down. If you ignore the errors you get a faily full but unhelpful list of errors from the wizard in a table.
Things I have worked out so far are:
(1) Rebuild all files.
(2) Validate and recover the database as this gets rid of some tmp files that are hagging around.
(3) No spaces in table names, you have to rename them and edit every form, view etc.
(4) Go into every form/view and check they are correct, I got caught with some historical ones that were no longer valid.
(5) Check all tables for field names or indexes that are reserved words. If you always prefix table ids you are fine but I found a table like this.
(6) I cant get default value field validation scripts to work (it cant find them) so Ive had to change how I do things. Luckily these were for incrementing counts etc so Ive managed to replace them with the new incrementing field type.
(7) Commands in indexes dont work.. i.e. an index on UPPER(<field_Name>). Havent worked this one out fully yet.
As you get through the above you will find most loads etc work OK although some it can not bulk update but it does offer to do it the old way.
I hope this helps.
Regards