gEDA-user: Rip up selected rats question, layer color

[toaster2@xxxxxxxxxxxx]

Thanks to all who gave me advice on the mounting hole question. I would like 
two more please 

1 The menu allows to auto route selected rats, but not the rip for selected 
rats, i.e. it allows only to rip the the whole board. Is there an easy way to 
just rip a selected portion of auto routed rats that I select by dragging a 
rectangle around the area of interest? Also, can I just click a portion of a 
poly-line autorouted track and get the program to figure out all the line 
segments so I don't have to delete each individual segment?

2.Setting the track colors for 2 layers. Is the below procedure OK?
I am doing a 2 layer board and grouped the eight possible layers into 2 doing 
Settings->Edit Layer groupings. After Connects->"auto-route all rats" , I get 
tracks in a dark red and medium red. I regrouped the medium red "component" 
into group 1, and left the "GND-comp" "Vcc-comp" "turquoise unused" and 
"green unused" into group2. After ripping apart the auto-routed rats, I get 
two colors for my tracks as I expected. The printed output files of back.ps 
and front.ps seem to be all right. Is this going to give me correct gerber 
files, or am I going to mess something up? Is there any reason at all for me 
not to do this color setting technique?
Thanks,
Frank