As far as I know there is no automatic way to adjust DST. There is the 'UseDST' system variable but this just sets the time ahead or back one hour--the programmer has to set the variable.
Here is some code I've used in the past to control daylight savings time. I can't take full credit for this--I think I adapted it to Crimson from a snippet I found in some other forum. Put this in your global OnTick action to run once per second.
Code:
// Daylight Savings Time runs from 2nd Sunday of March to 1st Sunday of November
int month := GetMonth(GetNow());
int date := GetDate(GetNow());
int previousSunday := date - GetDay(GetNow());
// January, February, and December are out
if (month<3 || month>11) UseDST := false;
// April to October are in
else if (month>3 && month<11) UseDST := true;
// In March, we are DST if our previous Sunday was on or after the 8th
else if (month==3) UseDST := (previousSunday >= 8);
// In November we must be before the 1st Sunday to be DST
// That means the previous Sunday must be before the 1st
else UseDST := (previousSunday <= 0);