[Tininha]

Thanks, but I've managed to solve the problem without that app.

For the ones with the same trouble, here's my solution, after the help of helf:

1. I tried to find z4root in the playstore, and find out that Google forbid any root apps in the store;
2. Considering that in the first 5 times that I updated and/or 'reformatted', if we can say that, my 3 eDGe's, I've used the ES Explorer to modify build.prop, I used Root Checker to confirm that the PE was rooted - wich was;
3. I tried 3 more times, unsuccessfully, to modify build.prop, using ES Explorer;
4. Finnaly, I downloaded Root Browser and was able to made the modification.

Now everything is ok again - even considering that Documents to Go isn't the best office app that exists. I prefer Quick Office, but I really like to be able to open my pdf files in the tablet without have to open an app first.

But thank you. Ou obrigada...