Incremental Simple Copy Backup: Possible to access files from the previous jobs?

Dear all,

I have just installed Comodo Backup. The software looks great, however, I have one problem I can not solve. To save backup drive storage space, I prefer using Incremental Backups. Incremental Backups have however one serious disadvantage: if any of the incremental backups ends up corrupted, all the subsequent backups jobs will be worthless, as the link to the base backup will be broken. For this reason, I would like to use simple backup, so I can get to any previous files, as they are stored in their original format without compression.

This means, I would like to perform backups using the combination of: Incremental Backups + Simple Copy.

I have performed several tests. As I see, after every incremental backup, the base files are overwritten. Thus, I do not have archive of the files from the previous backups. Am I missing here anything? Is it possible to perform simple copy incremental backups, and still keep the copy of the files backed up from the previous incremental backup jobs up to the creation of the base backup?

I would like one more question: what is the recommended number of incremental backups, after I should recreate base backup? May I have say even 30 incremental backups and only one base backup?

Thank you in advance.

Would anyone know, please? I think, for experienced users, my questions should not be difficult.