Hi,

The best way to map old links to current ones is following:

1) Configure the application to allow custom URL extensions - instructions here in DevGuide.

2) Enable following settings in Site manager -> Settings -> URLs and SEO
- Allow permanent (301) redirection and
- Redirect document aliases to main URL
More details about those settings are also in DevGuide - Development - Page processing and URLs - URL format and configuration

3) For each page, add the aliases of old URLs similarly like described in another DevGuide article on multiple document aliases. You can manually specify appropriate extension (e.g. ".htm") if you don't have enabled it in general (in site settings).

After this setup, the old url will be accessible. Visiting such url will redirect the visitor to the current valid page.

Regards,
Zdenek C.