trkMax is something you're setting in a <fieldval> on the item, right?
You're not setting it in a script?
Because <creation> scripts are run only one time, when that pick is first added to the character, and then never run again, if you're setting the trkMax in a script, then it's too late - the creation script has already run.
If you are setting the trkMax in a script, then your creation script would need to look like this:
Code:
<creation><![CDATA[
~if we'll be resetting to our maximum, then set our starting value to a very big number, which will later be corrected to be the maximum by the field's <bound> script
if (tagis[Helper.ResetMax] <> 0) then
field[trkUser].value = 9999999999
endif
]]></creation>