Hi,
Well, if you have the lookup-table in a for-next loop like you are currently showing it will run thru that loop and then continue with the reset of the code. You have to move the NEXT so that it actually updates the dutycycles registers with the value retreived from the table before looking up the next value.

For duty = 0 to 44
Lookup.....
Set dutycycle
Pause whatever
Next

Then, in order to get you three phases you either need to have three lookup tables or you need to index the same lookuptable by offsetting the index by 1/3 for each phase and keep track of when to "roll over" and start at 0 again for each phase.