First, see this thread for examples of scripted finds. You'll find examples where a set field step is used to specify a calculated value as find criteria: Scripted Find Examples
then you can use a set field step such as:
Set Field [ YourTable::dateFIeld ; Get ( CurrentDate ) & "..." & Get ( CurrentDate ) + 180 // approximately 6 months ]
Set Field [ YourTable::DateFeild ; Get ( CurrentDate ) & "..." & Date ( Month ( Get ( CurrentDate ) + 6 ; Day ( Get ( CurrenDate ) ) ; Year ( Get ( CurrendDate ))) // exactly 6 months from today ]
Note: there are a lot of parenthesis in the second example and I could easily of omitted one by accident when I typed this up.
thanks a lot for your answer. maybe I'm just not thinking straight here, but I now have the script according to this: Set Field [MyTable::MyField; Get ( CurrentDate ) & "..." & Get ( CurrentDate ) + 180] and when I run it, I get an error message saying that this field is not modifiable.
I would assume is because it's a calculation field? a quick search had me suggesting that I should uncheck "Prohibit modification of value", but I can't find it. any help to point me in the right direction would be much helpful!
Please take another look at the example scripts from the thread I suggested in my last post.
The set field step must be executed while in Find mode, not Browse mode.
Enter FInd Mode 
Set Error Capture [on]
Perform Find 
is the basic outline used for each of the scripted finds in that thread.
thanks a lot, that was it.