Disclaimer: I aim to build a self contained pen drive with my application inside, so no matter about updates. Maybe I'm looking at the wrong linux distribution to do this... Please let me know if you think so. I've tried knoppix and even lubuntu, but they don't come with enough "drivers" for Unity3D to work.

Creating a custom live persistent pen drive is a real pain and I'm trying for 1 day without any success. Sure, being able to do it would probably be ideal and occupy the minimum space.

Using the installation image on a pen drive, however, is good enough and is really easy to create. We can even do it from any OS, using UNetBootin, LiLi USB Creator or some other methods. Straight forward.

Some recommend installing it on a pen drive. But that requires a lot of space and, I believe, it won't behave as good as something meant to be installed on a usb disk, because of memory management.

So, there are only a few negative points on using the installation image that I can think of.

Question here, is how to remove those drawbacks:

• Having to press "Try Ubuntu". That's the big one. Couldn't find how.
• Unable to load everything on memory and keep on running without the pen drive (like this)
• Unable to remove "Install Ubuntu 12.04 LTS" app.
• Setting the ISO to use maximum amount of space for the OS will leave pen drive with zero space left and any file saved within it from ubuntu is inaccessible from the outside (when plugin the pen drive and not booting from it).

Am I missing something? Can those points be fixed?