I don't think there is an easy way to do it. You can do a material search if you are looking for specific material combinations but that is the only way I can think of of going about doing it.
SCID Filtering

Thanks Martin, I thought about something like that, but unfortuantely the number of combinations is pretty Daunting. So for now, Im just scrolling through my problems data base doing a visual check for 7Pieces or less and saving hits to a seperate file which I may post to the Puzzles thread when I am done.
but if SCID had some sort of head count function im sure it could do far more in 4 sec than I have done in 4 hours. BB.

I have a pretty large pgn Download of problems in FEN format; is there anyway to filter for positions with 7 pieces or less? Thanks BB.
I don't know how to do it in Scid, but it might be possible in CQL (Chess Query Language). Do you only want the 7 pieces or less criterion to apply to the initial position in a game fragment, or any position in a game fragment?
CQL can strip out all games fitting the criterion into an output PGN file, but it can't automatically create multiple new Fen positions from a single game. (I'm not sure I'm explaining it clearly. )

Also, CQL isn't hard to run. It's a little standalone program, no installation required; Just unzip it and run it. The hardest part is creating the CQL file that tells it how to do a particular search. I can give you that info.
Just so you know, I'm not an expert at CQL. I've only created a few of the simplest search files. Most of the CQL files are WAY over my head.

I have a pretty large pgn Download of problems in FEN format; is there anyway to filter for positions with 7 pieces or less? Thanks BB.
E-mail me the fen file. It will only take me a few minutes to write a short script to filter out all games with 7 pieces or less. I will then e-mail you back those filtered games.

Thanks Guys,
I have created a file by hand that contaiins 500 Minitures, which will keep me entertained quite some time.
http://www.chess.com/download/view/500-miniture-chess-problems
I have a pretty large pgn Download of problems in FEN format; is there anyway to filter for positions with 7 pieces or less? Thanks BB.