(2-part post):
I suspect that you might have lost the instructions ;-)
I use an IP3000. This shares its instruction book with the IP4000 but it also came with a completely separate 'CD-R Print Guide'. This makes no reference to any particular model, so I assume that the instructions are common to many Canon printers. The guide is the size of a paperback book but that's only because it's in 12 languages. Hopefully, I can summarise its content fairly easily:
1. Start CD-LabelPrint
2. Click 'New'.
3. Click the 'Select Paper' icon. (Its on the next row under 'File', 'Edit', etc.)
4. Under 'Print Genre', select 'CD-LabelPrint'.
5. Under CD Type, select 'Standard CD (12cm)'.
6. Click OK.
7. Edit the label image. (Check the Help file if you need further information).
8. Click 'Print'
9. Click 'Printer'