If you really want to use bash as shell, the line
Code:
#!/bin/bash
must be the first line of the script
OMG How could I have forgotten that!?!?!!!

don't put commands to variables, only command parameters, it makes code more readable and more flexible, like this:
Understood. I'll make those changes asap.
add a column with numbers (or other simple strings) as first column for zenity's radiolists, You won't need to use grep to recognize choices...
Good idea. That eliminates the need to have a special unique word in each option.
... and instead of using "if...then...fi" use "case $var in .... esac" statements, for example:
Code:
I'll give that a shot. I've never used the case syntax before so I'll mess with some test scripts to see how it works and get a feel for it, and if its cool I'll make those changes

lol ....sniff....but grep is so dang cool!
DON'T use "kill -9", it is last resort signal. Just use "kill" (defaults to kill -TERM). Besides - I think, that "Creating build environment." window is not needed, whole process takes miliseconds, so there is no need to display progress at all.
OK I'll throw out the -9 its just a bad habit of mine. I'll eliminate that window too, as I also noticed that it appears only momentarily, and basically because of a sleep hack.

implement MAX_RETRIES for source retrieval
That was listed in my caveats but not in my todo list for some odd reason. Hehe. Not sure why not, but I was basically pondering the inplementation. I'd been working on a way to do it. I had been thinking about a for loop, that repeated a command until the count ran down. You way looks cool and complex, I'll mess with trying to understand it

add error handling wherever possible and add appropriate messages (I hate messages like "Unknown error has occured")
Yea... it was on my mental todo list.

avoid putting zenity in background (maybe use "|" as in above example)
Not sure what you mean there. Heh... My skull is a bit thick.
always set one of choices in radiolists to TRUE
I don't understand this one either.
Enough for now ...?
BRING IT ON![/color]