Teensylu Bootloader Trouble

To sum up a week of frustration and googling. I finished building my Prusa i3, and now I'm attempting to get it moving.
I'm using a teensylu board, so I started following the instructions on the teensylu page of the reprap wiki, and ran into a problem with Atmel FLIP. Basically, it said I was missing AtLibUsbDfu.dll, and after scrambling about on the internet, I solved that issue by also installing winAVR, which had the files it needed.
Then, however, com.atmel.flip.ispexception told me it "could not open USB device." Google yielded several methods that didn't do anything about the problem, or hit the same problem. Specifically, avrdude hti the same problem, with both the DFU and CDC bootloaders.
Any advice, suggestions, or questions would be appreciated. I'm trying to do this on my old laptop, which is running windows 7, if that helps at all.

So... no responses? Ok, updates, then.
Turns out that the problems with avrdude stemmed from a tutorial I had been following, which had purported to flash the bootloader without a usbtinyisp, but used it anyway. Seeing as I'm trying to do this solely over usb, and do not have a ISP, that method is out. This brings me back to FLIP, which continues in saying "could not open USB device." Any conjecture would be appreciated.

Make sure you have the correct port for the device. You may need to poke around in device manager to get things set up. I can tell you that the devices are not always where you left them, because , especially if you have a ton of crap hooked up, windows has a way of assigning ports almost at random, every time you restart it. I have a nano for example that likes 3 just as much as it likes 4, and if the software is looking on 3 and the board happens to think it's on 4, well, you get the picture.

Ok, here are some tips ive found help...

Turn off your teensylu, pull off the jumper labeled 'ALE' on my rev0.8 board its just to the right of the teensy chip. turn it back on, and look for your serial port, it should be different now, on my mac os x system, it was previously /dev/tty.USB12321, then it changed to /dev/tty.USB1242
this will enable flashing though arduino environment.

next you need to install the teensylu board info, prjc.com, make sure to install all the options/libs

next up I found some info on the GEEETECH wiki:

i found it at: [www.geeetech.com] - These instructions are all i had, and got it working.

Essentially you need to be able to select: "[BootloaderCDC]Teensylu/Printrboard" from the 'board' menu in the arduino IDE

once you've done that, you can upload away, I've run most arduino sketches on it, including blink and the various hello world serial ones.

Thansk for the suggestions, I've made some more progress on it now. However, in the intervening time, a friend of mine gave me a Mega, so now I'm using that instead, since there is FAR more documentation on it. Thanks anyway! perhaps now I can use the teenyslu for something else...