Hi Jussij
I don't know if you'll be able to fix this but here goes. This problem existed in 3.95z and I just discovered in exists in my evaluation copy of 3.96n. It was my main reason for trying the evaluation copy.
After Zeus is open for a while ( usually a few hours, occasionally overnight) double clicking on an entry in the xfgrep window no longer works. The status line says:
The line contains no error. Please check the compiler or project regex settings.
I exit Zeus and then restart Zeus again and it is better. for a while.
Jack
Problems with xfrep windows
Hi Jack,

There will be a new Zeus 3.96o version out soon. Hopefully it will be better behaved
Even though the fail loads, is the the line is still displayed as red or green (i.e an error or warning line)
Cheers Jussi
You are right, this is going to be a tough one to track downI don't know if you'll be able to fix this but here goes.

It was my main reason for trying the evaluation copy.
There will be a new Zeus 3.96o version out soon. Hopefully it will be better behaved

The line contains no error. Please check the compiler or project regex settings.
Even though the fail loads, is the the line is still displayed as red or green (i.e an error or warning line)

Cheers Jussi
Jussij question:
Even though the fail loads, is the the line is still displayed as red or green (i.e an error or warning line)
Answer:
All lines are in black which has always been the case for me.
I checked in the color options. Red is selected for errors, green for warnings. The dialog box title says "Properties[C/C++ Document Type]". I set Zeus display view combo to Tool Output View., select Category as Errors or warnings.
Jack
Even though the fail loads, is the the line is still displayed as red or green (i.e an error or warning line)
Answer:
All lines are in black which has always been the case for me.
I checked in the color options. Red is selected for errors, green for warnings. The dialog box title says "Properties[C/C++ Document Type]". I set Zeus display view combo to Tool Output View., select Category as Errors or warnings.
Jack
There is a new Zeus release that hopefully fixes this bug 
The patch can be found here: http://www.zeusedit.com/forum/viewtopic.php?t=1863
Cheers Jussi

The patch can be found here: http://www.zeusedit.com/forum/viewtopic.php?t=1863
Cheers Jussi