I used RokCandy with Joomla 1.5 some years.
And I tested RokCandy with Joomla 1.7.0.
All worked OK.
But macro not used switch from category.
Macro work if category swith to other language or of category.
If you switch on support category option (ON/OFF and language) - RokCandy will be ready for Joomla 1.7.0
If you want I can help you as tester of new release or etc.