Vega,
This is a very basic filter that you should have been able to build after completing the Equis Formula Primer. The easiest way to handle any programming cahllenge is to break the requirement into its smallest components.
In this case yuo want an exploration that concentrates on volume and price actions. We will deal with the filter conditions later, but lets start by making a new exploration with column that will display the data for our equities.
{Column A - Volume}
VOLUME
{Column B - Close}
CLOSE
{Column C -HHV}
HHV(H,128);
{128 daily bars is representative of about 6 months}
{if you want precise calendar based lookback}
{Is uggest using Jose's calendar tools}
You could run this exploration with no filter condition to see the results given by all stocks in the search, but you dont want to see all of the stock, you only want to see a selection that meets a specified criteria, so in the filter we start building our conditons.
Build one filter condition at a time and run the exploration each time (on a small handful of stocks, no need to do the entire exchange whilst we are still testing)
Lets start with the volume condition:
{filter}
ColA>100000;
Notice I used ColA here to refer to the value of Column A, it is up to you to whether you use ColA or V>100000 which will produce the same results
Run the exploration. Are the results as expected by out condition? Do all of the stocks return have a value in column A, the volume column greater than 100000? Are there any errors?
Then we add to the criteria, using the AND condition (because you are looking for multiple criteria where each criteria must be met)
{flter}
ColA>100000 AND
ColB>10;
NOTE: this could also be written:
{flter}
V>100000 AND
C>10;
Run the exploration. Are the results as expected by the condition? Do
all of the stocks return have a value in column A, the volume column
greater than 100000 AND a closing price in column B greater then 10? Are there any errors?
Then we add to the criteria,
{filter}
ColA>100000 AND
ColB>10 AND
C<(HHV(H,128)*0.5)
for the retracement.
NOTE: There is a big difference between a stock having a price 50% of the recent high, and a stock that has retraced 50% of the HHV-LLV trading range. Make sure you understand exactly what you are asking for in the filter as MS will show you the results for the conditions you actually code, not for the conditions that you think you mean.
Hope this helps.
wabbit
MS: 6.52 EOD, 7.x EOD, 8.0 PRO, 9.2 PRO w/QC, 10 PRO w/QC & MDK
For custom MetaStock programming : http://www.wabbit.com.au
My SkyPE status : 
My SkyPE account : wabbit.com.au