indicator reading problem

 
Hi all,
I have problem with reading signals from indicator to expert.
I attachet indicator and screen there http://www.gorski.vel.pl/mysite/pliki.php5?idthema=13

The problem is like this:
This indicator (with you can get from here http://www.gorski.vel.pl/mysite/files/file_27.mq4) shows red line and blue line when the trend is down or up, but when the trend is unknown the indicator dont draws any line. Like on the screen here http://www.gorski.vel.pl/mysite/files/file_28.GIF

And the question is simple - how to read to expert these signals - for this time i done it that:

double s1 = iCustom(Symbol(),5,"trendline",20,0,1);
double s2 = iCustom(Symbol(),5,"trendline",20,1,1);
double b1 = iCustom(Symbol(),5,"trendline",20,2,1);
double b2 = iCustom(Symbol(),5,"trendline",20,3,1);

and if s1 and s2 wasn't empty it was a sell signal , when b2 and b1 wasn't empty it was a buy signal, and thats ok but it don't shows the blank regions. Could somone help me to read the blank regions ?