If you only have games of a single limit type (fixed, pot, or no limit), but of more...

If you only have games of a single limit type (fixed, pot, or no limit), but of more than one blind size, then you won't see the 'NL', 'PL', 'FL' checkboxes in the Limits: section of the filters.  When you check the 'All' checkbox, the individual size checkboxes won't be checked, because the code relies on the 'NL', 'PL', 'FL' checkboxes being there to do it.  This fixes the problem.

To reproduce: have only 2 hands in the database, both no limit, one 2nl and one 5nl.  Click 'None' then 'All'.  The 2nl and 5nl checkboxes will turn off when you click 'None' but not turn back on when you click 'All'.