Sean,
This is currently only possible with a Custom MySQL command run after Import with PhpMyAdmin, often available from your control panel.
To set the user to receive followup 11 next dailymail you must set their "cseq" and "cdel" values to "11" and "0" respectively.
Let's say the date is Dec 31st, 2003 and you're using List 1.
Import your users then run the following query in PhpMyAdmin:
update lm_users set cseq = '11', cdel = '0' where list = '1' and dateadd = '2003-12-31' and refurl = 'Imported'
Note that ANY users on this list that were imported on this date will be modified, so don't run it if you have imported users who you DON'T want this to affect.
The next release features welcome, confirmation, signup-xtra.php, and the ability to set the followup for new imports.