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user_id=218539

Well, this feature is in CVS since yesterday:)

Your queries could be performed as:

1. Created: from -1d

2. If "opened" - is it a synonim for "created" then Created:
from -1w (or just -1w)

3. Activity: -1w and AssignedTo: assigned to me

It is a bit harder to perform a Stefan's query with classic
tracker, but possible:

notice that activity on issue usually stops when issue is
closed, so you can search like this:

Activity: from {milestoneAdate} to {milestoneBdate} and
Status=resolved

You should substitute {milestoneAdate} and {milestoneBdate}
with actual dates.

However some activity is actually possible after closing
issue (e.g. change of priority). To be more precise, you can
add one more property to Issue schema - close_date=Date() -
and write a reactor, that changes it to 'now' when issue's
status becomes 'resolved' and to '' when issue status
becomes other than 'resolved'. As I did for my tracker.