Hey, that first link is from me. That post was for 6.0, that has to be why the crashes. The gapps version will be different for 7.1. if i recall correctly, i downloaded the script from geektillithertz and the gapps from opengapps.
So for 7.1 all you need to do is the following instead of step 2:
1) Download appropriate version of gapps from opengapps
2) Copy the script "gapps_script.sh" from my folder into the corresponding location for new gapps.
then continue the following steps there. I think that should work, let me know how it goes, good luck.