I just came across this and thought I would check it out.
I've been coding Lua for GMod for quite a while now and I thought I would share what I think are some of the pitfalls, I don't want this to sound like I'm full out "bagging" your program but I think it might end up sounding like that so warnings in advance.
The first thing I noticed was the lack of the ability to add a folder of Lua files recursively, manually adding files is a real pain.
Then I noticed the lack of a proper tree view of folders and files in the project explorer, the function tree view is nice, but without folders my project immediately looked like a mess.
A small niggle is that you can't close a tab with a simple middle click, instead opening the tab and hitting the close icon. No it's not going to kill me, but it would be nice.
Now I didn't really have a good look for this so forgive me if it is actually there somewhere, but it would be nice to be able to edit the syntax highlighting for different mods or whatever other reason.
Anyway, I hope that didn't sound too bad, I hope you can make this a good application to use.