simple system

[POMPATIS@xxxxxxx]

Greetings:

I have a very simple system i would like to write in metastock, but i am 
lousy at programming.  Any help is hugely appreciated.

Following is the system in english stated 2 ways:

first way:

Buys:  1) requires the average close of x days to be greater than the same 
average close y days ago. 2) requires the close to be less than the close y 
days ago. 3) requires the close to be greater than the close y + x days ago.
Then buy on the open the next day.

Sells are the inverse of the buys and the system simply reverses upon a new 
signal.  Protective stops have not been determined.

Now in plain english (I think):  let x = a 20 period exponential ma, and y is 
a 20 period exponential ma displaced by 4 periods.  Then the average close of 
the previous 20 days must be greater (for buys) than the average close of the 
last 20 days starting 4 days ago.  Then today's closing price must be less 
than the closing price 4 days ago.  Finally, the close must also be greater 
than the close of 24 day's ago.

I tried to program this but do not know how to formulate a displaced ma in 
metastock.  Thanx for any help folks.

Sincerely,

KM