Blogger>>WP problem with calendar/WP entries

After a lot of trial and error, I’ve imported about 300 Blogger entries into my WP blog; I’m using WP 1.5.2 with a modified “Stucco” theme. I’ve gotten this far by using the Codex and support, but haven’t found anything for this specific set of problems, which is suspect has a single root cause:

1. On my sidebar (you can see it at https://www.dieiscast.com, clicking on a month with ex-Blogger posts shoots the used into a directory; all posts are unformatted.
2. Trying to “manage” the posts shows them as untitled blocks of code and text.
3. For Sept. 2004, which has both WP and ex-Blogger posts, the sidebar link sends the user to a directory with only the Blogger posts, but in the “manage posts” admin section, only the WP posts are visible.
4. When doing a keyword search, WP returns both WP and ex-Blogger posts, perfectly formatted. For example:
https://www.dieiscast.com/index.php?s=bug+fights
The 1st 2 posts are WP; the last is ex-Blogger

I’d have thought that I was just importing incorrectly (which may be the case anyway), but then why are the posts formatted when discovered by a search?

I haven’t been able to find anything to address these problems, and I’d really appreciate any help.