What Red has suggested is correct.

Here is what I do manually until the new FMA Cell Pro devices and chargers are released for sale.

[ul][*] After charging, measure the voltage of each cell using the taps (should be 4.2v)[*] If the voltage of each cell is within 0.01v to 0.05v of the others then you are ok[*] If not, set the charger to 1s and charge across the taps where you meaured the low voltage
[/ul]

If you use a smart charger like the Apache 2500, you are fairly safe from making a mistake as the charger will flash on any invalid setup.

In summary, the taps simply allow you to measure the individual cell voltages if you connect a voltmeter across them correctly or if you connect a charger like the Apache 2500 across them correctly when set to a 1-cell charge with a reasonable current setting like 1C.

Unless you have used your Lithium pack extensively or have created a larger pack by connecting several smaller ones together, you will not likely see an unbalance.