I really think that you have put a lot if time and effort in to this and it looks very nice! Keep up the good work!
I also realize it's still in alpha.
I like how I wasn't overwhelmed with features. Some programs feature way too many options to the point where it's annoying. It was nice to have only a few options that I could understand.
The standard functions (love.load(), love.draw(), etc.) were not highlighted.
When you had a colon (:) and did a function (such as :getWidth()) it was no highlighted.
The Smart Tabbing added an extra space (I don't know if this was optional or not, but I thought I'd let you know).
For once, I finally agree with Raidho36, you need to implement shortcuts. When I tried to cut something (ctrl + x) it said there was an error and asked if I wanted to keep trying to use it or close the program. I tried to continue, but the error made it impossible to continue, reappearing every time I clicked.
I like how the conf.lua is asked at the start of the project! That's very smart of you!
With the statements above in your mind, I know it's not going to be perfect (it is beta) and I appreciate that. It still preforms solidly and I like it.
P.S: I have a Windows 8 and from what I've heard, you're not missing a ton. You can't have a keypressed and move your mouse at the same time is an annoying flaw (which can be overcome with a plugged in mouse).
ANYWAY, back on topic:
Nice IDE! I think I will switch to it once it is in a fully functional condition!
.. I am adding keyboard shortcuts in the next update, as it is a feature that should have been there from the beginning I just never got around to it. And I will be fixing the syntax highlighting also, not in the next update but after the HTML5 update.