It might differ from setup to setup. I'm no expert, but I'd suggest:

1) Make sure you uninstall the old version of LimeWire.

2) Don't go crazy with disabling a lot of extensions - I would think (hope) that only the Contextual Menu extension is needed to be disabled. (On my Mac, I also disabled a 3rd party extension called "IdleTime," which came (I think) with my DSL install kit (I disabled it after reading how certain internet "spyware" can mess-up LimeWire and make it do weird things - however, I did this before finding out about the CM extension conflict, and it still didn't run right until I disabled the CM extension).

3) Restart the computer

4) Install LimeWire 1.7 - and after it is installed, double its memory allocation. (I have mine set for 12750 K, but I don't think I needed that much).

Other than that, I don't know what to suggest. You didn't mention what happened when you restarted your computer - what it was that made it seem like you had to reinstall it every time you reboot.

I hope this works, 'cause I wanna download all your files...