Ah!! anyhow the builder recquires design time .
An idea only ,you can just when build the cursor issue in code

sele cursortemp
copy to mytable_ondisc.dbf 

And then work at design time with this table mytable_ondisc.dbf & builder.

for more infrmation can also read http://fox.wikis.com/wc.dll?Wiki~RptEngin
(can execute programmatly a report with this code with a pre styled/formatted report( using wizards))